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-# Phase 4 Implementation Progress
-
-**Status:** 22/68 tasks completed (32.4%)
-
-**Test Coverage:** 170 unit tests, all passing ✅
-
----
-
-## Completed Modules
-
-### 1. Authentication Infrastructure
-- ✅ JWT Service (access token + refresh token)
-- ✅ Password Hasher (bcrypt, cost=12)
-- ✅ Session Store (Redis-based)
-- ✅ Email Service (SMTP with templates)
-
-### 2. User Authentication Flow
-- ✅ User Registration (with email verification)
-- ✅ Email Verification
-- ✅ User Login (JWT + Session)
-- ✅ User Logout (single device / all devices)
-- ✅ Password Reset (email-based)
-
-### 3. Workspace Management
-- ✅ Create Workspace
-- ✅ Invite Members (with email invitation)
-- ✅ Accept / Decline Invitation
-- ✅ Remove Members
-- ✅ Leave Workspace
-- ✅ Update Member Role
-- ✅ List Workspaces (user's all workspaces)
-- ✅ Get Workspace Detail
-- ✅ List Members
-
-### 4. Permission System
-- ✅ Permission Checker (role-based access control)
-- ✅ Role Permissions Mapping (Owner/Admin/Member/Viewer)
-- ✅ Permission Constants (workspace/member/project/asset)
-
-### 5. Subscription Management
-- ✅ Upgrade Subscription (Free→Pro→Enterprise)
-- ✅ Cancel Subscription (downgrade to Free)
-- ✅ Auto-configure quotas based on plan
-
-### 6. Quota System
-- ✅ Quota Checker (project count + storage usage)
-- ✅ Quota Status (usage percentage)
-- ✅ Warning Levels (normal/warning/critical/exceeded)
-- ✅ Update Storage Usage
-
-### 7. Repository Layer
-- ✅ UserRepository (interface + InMemory)
-- ✅ WorkspaceRepository (interface + InMemory)
-- ✅ WorkspaceMemberRepository (interface + InMemory)
-- ✅ WorkspaceInvitationRepository (interface + InMemory)
-- ✅ ProjectRepository (interface only, for quota check)
-
----
-
-## Remaining Tasks (46/68)
-
-### High Priority
-- [ ] API Routes Integration (FastAPI)
-- [ ] Database Migration Scripts (PostgreSQL)
-- [ ] PostgreSQL Repository Implementation
-- [ ] API Documentation (Swagger)
-
-### Medium Priority
-- [ ] Frontend Integration Preparation
-- [ ] Error Handling & Validation Middleware
-- [ ] Rate Limiting
-- [ ] Logging & Monitoring
-
-### Low Priority
-- [ ] Payment Integration (Stripe/Alipay)
-- [ ] Webhook Handlers
-- [ ] Admin Dashboard
-- [ ] Analytics & Metrics
-
----
-
-## Next Steps
-
-1. **API Routes** - Implement FastAPI routes for all use cases
-2. **Database** - PostgreSQL repositories and migration scripts
-3. **Testing** - Integration tests for API endpoints
-4. **Deployment** - Update deployment configuration
-5. **Documentation** - API documentation and user guides
-
----
-
-**Last Updated:** 2026-06-17 07:27 GMT+8