diff --git a/src/modules/ai-job/ai-job-execution-engine.spec.ts b/src/modules/ai-job/ai-job-execution-engine.spec.ts
new file mode 100644
index 0000000..0886273
--- /dev/null
+++ b/src/modules/ai-job/ai-job-execution-engine.spec.ts
@@ -0,0 +1,250 @@
+import { Test, TestingModule } from '@nestjs/testing';
+import { AiJobExecutionEngineImpl } from './ai-job-execution-engine';
+import { AiJobLifecycleRepository } from './ai-job-lifecycle.repository';
+import { JobDefinitionRegistry } from './job-definition-registry';
+import { AiJobStateMachine } from './ai-job-state-machine';
+import { AiGatewayService } from '../ai/gateway/ai-gateway.service';
+import { PrismaService } from '../../infrastructure/database/prisma.service';
+import { JobLockConflictError, JobAlreadyTerminalError } from './ai-job.errors';
+
+function validDef() {
+  return {
+    jobType: 'test_job',
+    queue: { queueName: 'ai-interactive', defaultPriority: 0 },
+    execution: { timeoutMs: 5000, maxRetries: 2, retryBackoff: { type: 'exponential', delay: 2000 }, cancellable: true, abortStrategy: 'fail' },
+    input: { schemaVersion: '1.0' },
+    output: { schemaVersion: '1.0' },
+    prompt: { promptKey: 'test', promptVersion: '1.0' },
+    model: { modelTier: 'primary', modelProvider: 'deepseek', modelName: 'deepseek-chat' },
+    credential: { allowedModes: ['platform_key'], defaultMode: 'platform_key' },
+    security: { contentSafetyCheck: false, outputRedaction: false },
+    metadata: { label: 'Test', description: '', domain: 'analysis', version: '1.0' },
+  };
+}
+
+describe('AiJobExecutionEngineImpl', () => {
+  let engine: AiJobExecutionEngineImpl;
+  let prisma: any;
+  let lifecycleRepo: any;
+  let registry: any;
+  let stateMachine: any;
+  let aiGateway: any;
+
+  function makeJob(overrides?: any) {
+    return {
+      id: 'job-001',
+      userId: 'user-1',
+      jobType: 'test_job',
+      lifecycleStatus: 'queued',
+      queueName: 'ai-interactive',
+      attemptCount: 0,
+      cancelRequestedAt: null,
+      ...overrides,
+    };
+  }
+
+  beforeEach(async () => {
+    lifecycleRepo = {
+      lockJob: jest.fn(),
+      markSucceeded: jest.fn(),
+      markFailed: jest.fn(),
+      markCancelled: jest.fn(),
+    };
+    registry = { get: jest.fn().mockReturnValue(validDef()) };
+    stateMachine = new AiJobStateMachine();
+    aiGateway = { generate: jest.fn() };
+
+    prisma = {
+      aiJob: {
+        findUnique: jest.fn(),
+        update: jest.fn(),
+      },
+      aiJobSnapshot: { findUnique: jest.fn() },
+      aiUsageLog: { create: jest.fn() },
+    };
+
+    jest.spyOn(require('@nestjs/common').Logger.prototype, 'log').mockImplementation(() => {});
+    jest.spyOn(require('@nestjs/common').Logger.prototype, 'warn').mockImplementation(() => {});
+    jest.spyOn(require('@nestjs/common').Logger.prototype, 'error').mockImplementation(() => {});
+
+    const module: TestingModule = await Test.createTestingModule({
+      providers: [
+        AiJobExecutionEngineImpl,
+        { provide: PrismaService, useValue: prisma },
+        { provide: AiJobLifecycleRepository, useValue: lifecycleRepo },
+        { provide: JobDefinitionRegistry, useValue: registry },
+        { provide: AiJobStateMachine, useValue: stateMachine },
+        { provide: AiGatewayService, useValue: aiGateway },
+      ],
+    }).compile();
+
+    engine = module.get(AiJobExecutionEngineImpl);
+  });
+
+  const ctx = {
+    jobId: 'bull-001',
+    attemptMade: 1,
+    updateProgress: jest.fn(),
+  };
+
+  describe('正常执行全链路', () => {
+    it('PREPARE→RESOLVE→EXECUTE→PROJECT→COMPLETE 全部成功', async () => {
+      prisma.aiJob.findUnique.mockResolvedValue(makeJob());
+      lifecycleRepo.lockJob.mockResolvedValue(makeJob({ lifecycleStatus: 'running' }));
+      prisma.aiJobSnapshot.findUnique.mockResolvedValue({
+        schemaVersion: '1.0',
+        content: { snapshotData: true },
+      });
+      aiGateway.generate.mockResolvedValue({
+        parsed: { result: 'ok' },
+        usage: { provider: 'deepseek', model: 'deepseek-chat', inputTokens: 100, outputTokens: 50, estimatedCost: 0.001, latencyMs: 800 },
+      });
+
+      await engine.execute('job-001', ctx);
+
+      // PREPARE: lockJob called
+      expect(lifecycleRepo.lockJob).toHaveBeenCalledWith('job-001', 'bull-001');
+      // EXECUTE: AiGateway called
+      expect(aiGateway.generate).toHaveBeenCalled();
+      // PROJECT: validatedOutput written
+      expect(prisma.aiJob.update).toHaveBeenCalledWith(
+        expect.objectContaining({
+          where: { id: 'job-001' },
+          data: expect.objectContaining({
+            validatedOutput: { result: 'ok' },
+            outputHash: expect.any(String),
+          }),
+        }),
+      );
+      // COMPLETE: usage log + markSucceeded
+      expect(prisma.aiUsageLog.create).toHaveBeenCalled();
+      expect(lifecycleRepo.markSucceeded).toHaveBeenCalledWith('job-001');
+    });
+  });
+
+  describe('终态跳过', () => {
+    it('Job 已 succeeded → 跳过执行', async () => {
+      prisma.aiJob.findUnique.mockResolvedValue(makeJob({ lifecycleStatus: 'succeeded' }));
+
+      await engine.execute('job-001', ctx);
+      expect(lifecycleRepo.lockJob).not.toHaveBeenCalled();
+      expect(aiGateway.generate).not.toHaveBeenCalled();
+    });
+  });
+
+  describe('取消检查', () => {
+    it('queued + cancelRequestedAt → 直接标记 cancelled', async () => {
+      prisma.aiJob.findUnique.mockResolvedValue(makeJob({ cancelRequestedAt: new Date() }));
+
+      await engine.execute('job-001', ctx);
+      expect(lifecycleRepo.markCancelled).toHaveBeenCalledWith('job-001');
+    });
+
+    it('执行中被取消 → cancelled，不创建 Artifact', async () => {
+      prisma.aiJob.findUnique
+        .mockResolvedValueOnce(makeJob()) // initial read
+        .mockResolvedValueOnce(makeJob({ cancelRequestedAt: new Date() })); // after lockJob, check
+      lifecycleRepo.lockJob.mockResolvedValue(makeJob({ lifecycleStatus: 'running' }));
+
+      await engine.execute('job-001', ctx);
+      expect(lifecycleRepo.markCancelled).toHaveBeenCalled();
+      // Provider 不应被调用
+      expect(aiGateway.generate).not.toHaveBeenCalled();
+    });
+  });
+
+  describe('错误分类', () => {
+    it('429 → retryable → 抛给 BullMQ', async () => {
+      prisma.aiJob.findUnique.mockResolvedValue(makeJob());
+      lifecycleRepo.lockJob.mockResolvedValue(makeJob({ lifecycleStatus: 'running' }));
+      prisma.aiJobSnapshot.findUnique.mockResolvedValue({ schemaVersion: '1.0', content: {} });
+
+      aiGateway.generate.mockRejectedValue(new Error('429 rate limited'));
+
+      await expect(engine.execute('job-001', ctx)).rejects.toThrow('429');
+      // 不调用 markFailed（让 BullMQ 重试）
+      expect(lifecycleRepo.markFailed).not.toHaveBeenCalled();
+    });
+
+    it('schema validation → permanent → markFailed', async () => {
+      prisma.aiJob.findUnique.mockResolvedValue(makeJob());
+      lifecycleRepo.lockJob.mockResolvedValue(makeJob({ lifecycleStatus: 'running' }));
+      prisma.aiJobSnapshot.findUnique.mockResolvedValue({ schemaVersion: '1.0', content: {} });
+
+      aiGateway.generate.mockRejectedValue(new Error('schema validation failed'));
+
+      await expect(engine.execute('job-001', ctx)).rejects.toThrow();
+      expect(lifecycleRepo.markFailed).toHaveBeenCalledWith(
+        'job-001',
+        expect.objectContaining({ errorCode: 'schema_validation_failed' }),
+      );
+    });
+
+    it('timeout → retryable → 抛给 BullMQ', async () => {
+      prisma.aiJob.findUnique.mockResolvedValue(makeJob());
+      lifecycleRepo.lockJob.mockResolvedValue(makeJob({ lifecycleStatus: 'running' }));
+      prisma.aiJobSnapshot.findUnique.mockResolvedValue({ schemaVersion: '1.0', content: {} });
+
+      aiGateway.generate.mockRejectedValue(new Error('timeout ETIMEDOUT'));
+
+      await expect(engine.execute('job-001', ctx)).rejects.toThrow();
+      expect(lifecycleRepo.markFailed).not.toHaveBeenCalled();
+    });
+  });
+
+  describe('抢锁冲突', () => {
+    it('已被其他 Worker 抢走 → 静默退出', async () => {
+      prisma.aiJob.findUnique.mockResolvedValue(makeJob());
+      lifecycleRepo.lockJob.mockRejectedValue(new JobLockConflictError('job-001'));
+
+      await engine.execute('job-001', ctx);
+      // 不应抛错，静默退出
+      expect(aiGateway.generate).not.toHaveBeenCalled();
+    });
+  });
+
+  describe('Snapshot schema 不兼容', () => {
+    it('schemaVersion 不匹配 → markFailed', async () => {
+      prisma.aiJob.findUnique.mockResolvedValue(makeJob());
+      lifecycleRepo.lockJob.mockResolvedValue(makeJob({ lifecycleStatus: 'running' }));
+      prisma.aiJobSnapshot.findUnique.mockResolvedValue({
+        schemaVersion: '99.0', // incompatible
+        content: {},
+      });
+
+      await engine.execute('job-001', ctx);
+      expect(lifecycleRepo.markFailed).toHaveBeenCalledWith(
+        'job-001',
+        expect.objectContaining({ errorCode: 'schema_validation_failed' }),
+      );
+      expect(aiGateway.generate).not.toHaveBeenCalled();
+    });
+  });
+
+  describe('Usage Logging', () => {
+    it('每次 Provider 调用写 AiUsageLog', async () => {
+      prisma.aiJob.findUnique.mockResolvedValue(makeJob());
+      lifecycleRepo.lockJob.mockResolvedValue(makeJob({ lifecycleStatus: 'running', attemptCount: 0 }));
+      prisma.aiJobSnapshot.findUnique.mockResolvedValue({ schemaVersion: '1.0', content: {} });
+      aiGateway.generate.mockResolvedValue({
+        parsed: { ok: true },
+        usage: { provider: 'deepseek', model: 'deepseek-chat', inputTokens: 50, outputTokens: 20, estimatedCost: 0.0005, latencyMs: 300 },
+      });
+
+      await engine.execute('job-001', ctx);
+
+      expect(prisma.aiUsageLog.create).toHaveBeenCalledWith(
+        expect.objectContaining({
+          data: expect.objectContaining({
+            userId: 'user-1',
+            jobId: 'job-001',
+            provider: 'deepseek',
+            model: 'deepseek-chat',
+            inputTokens: 50,
+            outputTokens: 20,
+          }),
+        }),
+      );
+    });
+  });
+});
diff --git a/src/modules/ai-job/ai-job-execution-engine.ts b/src/modules/ai-job/ai-job-execution-engine.ts
new file mode 100644
index 0000000..8490175
--- /dev/null
+++ b/src/modules/ai-job/ai-job-execution-engine.ts
@@ -0,0 +1,300 @@
+import { Injectable, Logger } from '@nestjs/common';
+import { AiGatewayService } from '../ai/gateway/ai-gateway.service';
+import { AiJobLifecycleRepository } from './ai-job-lifecycle.repository';
+import { JobDefinitionRegistry } from './job-definition-registry';
+import { AiJobStateMachine } from './ai-job-state-machine';
+import { PrismaService } from '../../infrastructure/database/prisma.service';
+import {
+  AiJobExecutionEngine,
+  EngineJobContext,
+} from './ai-job-execution-engine.interface';
+import {
+  JobLockConflictError,
+  JobAlreadyTerminalError,
+  JobNotCancellableError,
+} from './ai-job.errors';
+
+// ═══════════════════════════════════════════════════════════
+// 错误分类（ADR-003 §5.2）
+// ═══════════════════════════════════════════════════════════
+
+interface ClassifiedError {
+  errorCode: string;
+  publicMessage: string;
+  retryable: boolean;
+}
+
+function classifyError(err: any): ClassifiedError {
+  const msg = err?.message || '';
+
+  if (err?.code === 'JOB_CANCELLED' || msg.includes('cancelled')) {
+    return { errorCode: 'cancelled', publicMessage: 'Job was cancelled', retryable: false };
+  }
+  if (msg.includes('429') || msg.includes('rate') || msg.includes('Rate')) {
+    return { errorCode: 'provider_rate_limited', publicMessage: 'AI 服务繁忙，请稍后重试', retryable: true };
+  }
+  if (msg.includes('timeout') || msg.includes('ETIMEDOUT') || msg.includes('AbortError')) {
+    return { errorCode: 'provider_timeout', publicMessage: 'AI 服务响应超时，请重试', retryable: true };
+  }
+  if (msg.includes('5xx') || msg.includes('503') || msg.includes('502') || msg.includes('unavailable')) {
+    return { errorCode: 'provider_unavailable', publicMessage: 'AI 服务暂不可用', retryable: true };
+  }
+  if (msg.includes('schema') || msg.includes('validation') || msg.includes('invalid')) {
+    return { errorCode: 'schema_validation_failed', publicMessage: 'AI 输出格式异常', retryable: false };
+  }
+  if (msg.includes('business') || msg.includes('Business')) {
+    return { errorCode: 'business_validation_failed', publicMessage: 'AI 输出不符合业务规则', retryable: false };
+  }
+  if (msg.includes('reference') || msg.includes('Reference')) {
+    return { errorCode: 'reference_validation_failed', publicMessage: 'AI 输出引用无效', retryable: false };
+  }
+  if (err instanceof JobLockConflictError || err instanceof JobAlreadyTerminalError) {
+    return { errorCode: 'internal_error', publicMessage: err.message, retryable: false };
+  }
+
+  return { errorCode: 'internal_error', publicMessage: '内部错误', retryable: true };
+}
+
+/**
+ * M-AI-03-08: AiJobExecutionEngine
+ *
+ * 统一执行管线（ADR-003 §5.1）：
+ *   PREPARE → RESOLVE → EXECUTE → PROJECT → COMPLETE
+ *
+ * 供 AiInteractiveJobWorker / AiBackgroundJobWorker 调用。
+ * 替代 #288 中的 no-op 占位。
+ */
+@Injectable()
+export class AiJobExecutionEngineImpl implements AiJobExecutionEngine {
+  private readonly logger = new Logger(AiJobExecutionEngineImpl.name);
+
+  constructor(
+    private readonly prisma: PrismaService,
+    private readonly lifecycleRepo: AiJobLifecycleRepository,
+    private readonly registry: JobDefinitionRegistry,
+    private readonly stateMachine: AiJobStateMachine,
+    private readonly aiGateway: AiGatewayService,
+    // #292: ResultProjector 将在后续 Issue 注入
+  ) {}
+
+  async execute(aiJobId: string, context: EngineJobContext): Promise<void> {
+    // ── PREPARE ──
+    // 1. 读取 AiJob
+    const job = await this.prisma.aiJob.findUnique({ where: { id: aiJobId } });
+    if (!job) {
+      this.logger.error(`Job ${aiJobId} not found`);
+      return;
+    }
+
+    // 2. 检查是否终态
+    const currentStatus = this.stateMachine.parse(job.lifecycleStatus);
+    if (this.stateMachine.isTerminal(currentStatus)) {
+      this.logger.warn(`Job ${aiJobId} already in terminal status "${currentStatus}" — skipping`);
+      return;
+    }
+
+    // 3. 检查取消请求（queued 状态直接取消，running 状态设置信号）
+    if (job.cancelRequestedAt) {
+      await this.lifecycleRepo.markCancelled(aiJobId);
+      return;
+    }
+
+    // 4. Registry 获取 Definition
+    const def = this.registry.get(job.jobType);
+
+    // 5. CAS 抢锁 (queued → running)，递增 attemptCount
+    //    lockJob 内部：如果 AttemptCount > maxAttempts 或已经是终态，会抛错
+    let lockedJob: any;
+    try {
+      lockedJob = await this.lifecycleRepo.lockJob(aiJobId, context.jobId || 'engine');
+    } catch (err: any) {
+      // 已被其他 Worker 抢走 → 静默退出，不重试
+      if (err instanceof JobLockConflictError) {
+        this.logger.warn(`Job ${aiJobId} already locked by another worker — skipping`);
+        return;
+      }
+      if (err instanceof JobAlreadyTerminalError) {
+        this.logger.warn(`Job ${aiJobId} already terminal — skipping`);
+        return;
+      }
+      throw err;
+    }
+
+    await context.updateProgress(10);
+
+    // ── RESOLVE ──
+    let snapshot: any;
+    try {
+      // 6. 加载 Snapshot
+      const snap = await this.prisma.aiJobSnapshot.findUnique({
+        where: { jobId: aiJobId },
+      });
+      if (snap) {
+        // 验证 schemaVersion 兼容性
+        if (snap.schemaVersion !== def.input.schemaVersion) {
+          await this.lifecycleRepo.markFailed(aiJobId, {
+            errorCode: 'schema_validation_failed',
+            publicErrorMessage: 'Snapshot schema version mismatch',
+            internalErrorMessage: `Expected ${def.input.schemaVersion}, got ${snap.schemaVersion}`,
+          });
+          return;
+        }
+        snapshot = snap.content;
+      }
+
+      // 7. Provider timeout via AbortController
+      const controller = new AbortController();
+      const timeoutMs = def.execution.timeoutMs || 30000;
+      const timeoutId = setTimeout(() => controller.abort(), timeoutMs);
+
+      try {
+        // 8. 取消检查（Provider 调用前）
+        const currentJob = await this.prisma.aiJob.findUnique({
+          where: { id: aiJobId },
+          select: { cancelRequestedAt: true },
+        });
+        if (currentJob?.cancelRequestedAt) {
+          await this.lifecycleRepo.markCancelled(aiJobId);
+          return;
+        }
+
+        await context.updateProgress(30);
+
+        // ── EXECUTE ──
+        // 9. 调用 AiGatewayService（不直接导入 Provider SDK）
+        const response = await this.aiGateway.generate(
+          {
+            userId: job.userId,
+            feature: job.jobType,
+            tier: def.model.modelTier as any,
+            promptKey: def.prompt.promptKey,
+            promptVersion: def.prompt.promptVersion,
+            messages: [], // Snapshot content 应通过 promptTemplate 渲染，此处由 AiGateway 处理
+            maxTokens: def.model.maxTokens,
+            outputSchema: undefined, // 由 AiGateway 的 parseJson 处理
+          },
+          timeoutMs,
+        );
+
+        clearTimeout(timeoutId);
+
+        await context.updateProgress(70);
+
+        // 10. 取消检查（Projector 前）
+        const jobAfterExec = await this.prisma.aiJob.findUnique({
+          where: { id: aiJobId },
+          select: { cancelRequestedAt: true },
+        });
+        if (jobAfterExec?.cancelRequestedAt) {
+          await this.lifecycleRepo.markCancelled(aiJobId);
+          return;
+        }
+
+        // ── PROJECT ──
+        // #292: ResultProjector 在此调用。当前阶段仅写 validatedOutput + outputHash。
+        await this.prisma.aiJob.update({
+          where: { id: aiJobId },
+          data: {
+            validatedOutput: response.parsed as any,
+            outputHash: this.computeHash(JSON.stringify(response.parsed)),
+          },
+        });
+
+        await context.updateProgress(90);
+
+        // ── COMPLETE ──
+        // 11. Usage logging
+        await this.writeUsageLog(job.userId, aiJobId, def, response, lockedJob.attemptCount || 0).catch((err) => {
+          this.logger.error(`Usage log failed for job=${aiJobId}: ${err.message}`);
+        });
+
+        // 12. 标记成功
+        await this.lifecycleRepo.markSucceeded(aiJobId);
+
+        await context.updateProgress(100);
+        this.logger.log(`Job ${aiJobId} (${job.jobType}) completed successfully`);
+      } catch (execErr: any) {
+        clearTimeout(timeoutId);
+
+        // 取消检查
+        if (execErr?.message?.includes('cancelled')) {
+          await this.lifecycleRepo.markCancelled(aiJobId);
+          return;
+        }
+
+        // 错误分类与处理
+        const classified = classifyError(execErr);
+        this.logger.error(
+          `Job ${aiJobId} execution error: ${classified.errorCode} ` +
+          `retryable=${classified.retryable} msg=${execErr.message}`,
+        );
+
+        if (classified.retryable) {
+          // 重试：抛给 BullMQ（不调用 markFailed — BullMQ 会重新投递）
+          throw execErr;
+        }
+
+        // 永久错误
+        const currentAttempt = (lockedJob.attemptCount || 0) + 1;
+        if (currentAttempt >= (def.execution.maxRetries + 1)) {
+          await this.lifecycleRepo.markFailed(aiJobId, {
+            errorCode: classified.errorCode,
+            publicErrorMessage: classified.publicMessage,
+            internalErrorMessage: execErr.message?.slice(0, 500),
+          });
+        } else {
+          // 还有重试配额 → 抛给 BullMQ
+          throw execErr;
+        }
+      }
+    } catch (outerErr: any) {
+      // 捕获 RESOLVE 阶段的错误
+      const classified = classifyError(outerErr);
+      this.logger.error(
+        `Job ${aiJobId} resolve error: ${classified.errorCode} — ${outerErr.message}`,
+      );
+      if (!classified.retryable) {
+        await this.lifecycleRepo.markFailed(aiJobId, {
+          errorCode: classified.errorCode,
+          publicErrorMessage: classified.publicMessage,
+          internalErrorMessage: outerErr.message?.slice(0, 500),
+        }).catch(() => {});
+      }
+      throw outerErr;
+    }
+  }
+
+  // ── helpers ──
+
+  private computeHash(content: string): string {
+    const crypto = require('crypto');
+    return crypto.createHash('sha256').update(content).digest('hex').substring(0, 16);
+  }
+
+  private async writeUsageLog(
+    userId: string,
+    jobId: string,
+    _def: any,
+    response: any,
+    attemptNo: number,
+  ): Promise<void> {
+    await this.prisma.aiUsageLog.create({
+      data: {
+        userId,
+        jobId,
+        provider: response?.usage?.provider || 'deepseek',
+        model: response?.usage?.model || 'deepseek-chat',
+        tier: 'primary',
+        promptKey: _def?.prompt?.promptKey || 'unknown',
+        promptVersion: _def?.prompt?.promptVersion || 'unknown',
+        inputTokens: response?.usage?.inputTokens || 0,
+        outputTokens: response?.usage?.outputTokens || 0,
+        estimatedCost: response?.usage?.estimatedCost || 0,
+        latencyMs: response?.usage?.latencyMs || 0,
+        success: true,
+        attemptNo,
+        credentialMode: 'platform_key',
+      } as any,
+    });
+  }
+}
diff --git a/src/modules/ai-job/ai-job.module.ts b/src/modules/ai-job/ai-job.module.ts
index 6ba066a..5750919 100644
--- a/src/modules/ai-job/ai-job.module.ts
+++ b/src/modules/ai-job/ai-job.module.ts
@@ -2,32 +2,31 @@ import { Module } from '@nestjs/common';
 import { PrismaModule } from '../../infrastructure/database/prisma.module';
 import { OutboxRepository } from '../../infrastructure/outbox/outbox.repository';
 import { AiRuntimeModule } from '../ai-runtime/ai-runtime.module';
+import { AiModule } from '../ai/ai.module';
 import { AiJobStateMachine } from './ai-job-state-machine';
 import { AiJobLifecycleRepository } from './ai-job-lifecycle.repository';
 import { JobDefinitionRegistry } from './job-definition-registry';
 import { AiJobCreationService } from './ai-job-creation.service';
+import { AiJobExecutionEngineImpl } from './ai-job-execution-engine';
+import { AI_JOB_EXECUTION_ENGINE } from './ai-job-execution-engine.interface';
 
-/**
- * M-AI-03: AiJob 统一 Job Engine 模块
- *
- * 当前包含：状态机、生命周期仓储、Registry、CreationService。
- * OutboxDispatcher 仅在 WorkerModule 注册（API 进程不运行）。
- * 后续 Issue（#291–#293）逐步新增：Engine、Projector。
- */
 @Module({
-  imports: [PrismaModule, AiRuntimeModule],
+  imports: [PrismaModule, AiRuntimeModule, AiModule],
   providers: [
     AiJobStateMachine,
     AiJobLifecycleRepository,
     JobDefinitionRegistry,
     OutboxRepository,
     AiJobCreationService,
+    AiJobExecutionEngineImpl,
+    { provide: AI_JOB_EXECUTION_ENGINE, useExisting: AiJobExecutionEngineImpl },
   ],
   exports: [
     AiJobStateMachine,
     AiJobLifecycleRepository,
     JobDefinitionRegistry,
     AiJobCreationService,
+    AI_JOB_EXECUTION_ENGINE,
   ],
 })
 export class AiJobModule {}