fix(membership): replace hardcoded 1GB storage with API-driven quota

AIStudyApp/AIStudyApp/Features/Profile/ProfileViewModel.swift

@@ -11,11 +11,14 @@ class ProfileViewModel: ObservableObject {
     @Published var itemCount = 0
     @Published var cardCount = 0
     @Published var usedBytes = 0
-    @Published var totalBytes = 1073741824
+    @Published var totalBytes = 0  // M-MEMBER-01-CLOSE-01C: 来自 /membership/me，不再硬编码 1GB
+    @Published var storageUnavailable = false
     @Published var isLoading = false
     @Published var errorMessage: String?
 
     var formattedStorage: String {
+        if storageUnavailable { return "暂时无法获取" }
+        if totalBytes == 0 { return "加载中…" }
         if usedBytes < 1024 * 1024 { return "\(usedBytes / 1024) KB / \(totalBytes / 1024 / 1024 / 1024) GB" }
         return String(format: "%.0f MB / %d GB", Double(usedBytes) / 1024 / 1024, totalBytes / 1024 / 1024 / 1024)
     }
@@ -23,6 +26,7 @@ class ProfileViewModel: ObservableObject {
     func loadAll() async {
         isLoading = true; errorMessage = nil
         await loadProfile()
+        await loadStorageQuota()
         isLoading = false
         Task { await loadActivitySummary() }
         Task { await loadStats() }
@@ -41,10 +45,24 @@ class ProfileViewModel: ObservableObject {
         if let assets = await a { kbCount = assets.knowledgeBaseCount; itemCount = assets.knowledgeItemCount; cardCount = assets.reviewCardCount }
         if let storage = await s { usedBytes = storage.usedBytes; totalBytes = storage.totalBytes }
     }
+
+    // M-MEMBER-01-CLOSE-01C: 从 /membership/me 获取真实存储配额
+    private func loadStorageQuota() async {
+        do {
+            let membership = try await MembershipService.shared.myMembership()
+            if let storage = membership.entitlements?.maxStorageBytes, storage > 0 {
+                totalBytes = storage
+                storageUnavailable = false
+            } else {
+                storageUnavailable = true
+            }
+        } catch {
+            storageUnavailable = true
+        }
+    }
 }
 
 // MARK: - Raw API models
-
 struct AssetsResponse: Codable {
     let knowledgeBaseCount: Int
     let knowledgeItemCount: Int