docs: update documentation with Phase 3.8 fixes and production warnings

docs/archive/COMPLETED.md

@@ -4,6 +4,71 @@
 
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+## ✅ Phase 3.8 - Production Stabilization & Bug Fixes (2025-12-06 to 2025-12-09)
+
+**Status:** ✅ **DEPLOYED TO PRODUCTION**
+**Production URL:** https://spotlight.cam
+
+### 🔧 Bug Fixes
+
+1. **Admin Dropdown Persistence** (`3195ce3`)
+   - **Issue:** Admin dropdown disappeared after page refresh
+   - **Fix:** Added `accountTier` and `isAdmin` to `GET /api/users/me` response
+   - **Files:** `backend/src/routes/users.js`, `backend/src/__tests__/users.test.js`
+
+2. **Mobile Chat Scroll** (`b506df1`)
+   - **Issue:** Page jumped to top on new message (mobile)
+   - **Fix:** Changed from `scrollIntoView()` to direct container scroll
+   - **Files:** `frontend/src/pages/EventChatPage.jsx`
+
+3. **Polish Characters Support** (`d780b54`)
+   - **Issue:** Names with ąćęłńóśźż rejected by validator
+   - **Fix:** Updated regex to include Polish diacritics
+   - **Files:** `backend/src/middleware/validators.js`
+
+4. **WSDC ID Type Conversion** (`c6cea11`)
+   - **Issue:** Registration failed with WSDC ID (number vs string)
+   - **Fix:** Convert to string before Prisma save
+   - **Files:** `backend/src/controllers/auth.js`
+
+5. **Match Chat Message Display** (`1013d12`, `19700ff`, `c8de07a`)
+   - **Issue:** Sender couldn't see own messages in match chat
+   - **Fix:** Added nested user object to messages response
+   - **Files:** `backend/src/routes/matches.js`
+
+6. **Socket.IO Reconnection** (`a5a2c7a`, `c8de07a`)
+   - **Issue:** Match chat didn't work after reconnect
+   - **Fix:** Auto-rejoin room on reconnect event
+   - **Files:** `frontend/src/hooks/useMatchChat.js`
+
+7. **Docker Production Build** (`5db396e`)
+   - **Issue:** Production backend missing scripts directory
+   - **Fix:** Added scripts to Dockerfile.prod COPY
+   - **Files:** `backend/Dockerfile.prod`
+
+### ✨ Features
+
+8. **Real-time Validation** (`71d22cc`)
+   - Username/email availability check (debounced, visual feedback)
+   - **Files:** `frontend/src/pages/RegisterPage.jsx`, `backend/src/routes/public.js`
+
+### 📝 Documentation
+
+9. **Local Development Config** (`b0ca382`)
+   - Added `docker-compose.override.yml` support (gitignored)
+   - Added `.env.development.local` support (gitignored)
+   - Enables mobile testing without committing local IPs
+
+### 🚀 Production Status
+
+- **Deployed:** 2025-12-09
+- **Downtime:** None
+- **Database Changes:** None
+- **Breaking Changes:** None
+- **Tests:** 351/351 passing (100%)
+
+---
+
 ## ✅ Phase 0: Frontend Mockup (COMPLETED)
 
 **Completed:** 2025-11-12