test: improve test cleanup with selective deletion

- Replace deleteMany({}) with selective deletion by username/email/slug in:
  - events.test.js (target specific test users/events only)
  - matches.test.js (target specific test users/events only)
  - csrf.test.js (target csrftest user only)
- Replace delete() with deleteMany() for resilient cleanup:
  - matches.test.js (2 inline cleanups)
  - socket-webrtc.test.js (1 inline cleanup)
- Update TODO.md with test status and future UX/UI improvements

Test improvement: 189/223 passing (84.8%), up from 145/223 (65%)

docs/TODO.md

@@ -11,6 +11,75 @@
 **Also Completed:** 1.6 (Competition Heats System - Backend & Frontend) - ✅ COMPLETED
 **Progress:** ~72% complete
 
+### 🔧 CURRENT STATUS - Backend Tests (2025-11-20)
+
+**Test Status:** 189/223 passing (84.8%) - ✅ Significant improvement!
+- **Before:** 145/223 (65%)
+- **After fixes:** 189/223 (84.8%)
+- **Improvement:** +44 tests (+19.8%)
+
+**✅ Fixed:**
+1. Test cleanup - replaced `deleteMany({})` with selective deletion:
+   - `backend/src/__tests__/events.test.js` - selective deletion by username/email/slug
+   - `backend/src/__tests__/matches.test.js` - selective deletion by username/email/slug
+   - `backend/src/__tests__/csrf.test.js` - selective deletion by username/email
+2. Cleanup resilience - replaced `delete()` with `deleteMany()`:
+   - `backend/src/__tests__/socket.test.js` - all afterAll + inline cleanup
+   - `backend/src/__tests__/matches.test.js` - inline cleanup (2 locations)
+   - `backend/src/__tests__/socket-webrtc.test.js` - inline cleanup
+3. Socket tests fixes:
+   - Changed `eventId` → `slug` in socket event handlers
+   - Added `EventParticipant` creation before join_event_room
+   - Added safety checks before creating FK relationships
+4. Auth tests fixes:
+   - `app.test.js` - CORS origin localhost:8080
+   - `security.js` - added localhost:3000 to allowed origins (dev)
+   - `auth-phase1.5.test.js` - fixed error message expectations
+
+**❌ Remaining issues (34 failing tests in 3 test suites):**
+- `users.test.js` - ??? (unknown errors, needs analysis)
+- `events.test.js` - ??? (unknown errors, despite cleanup fixes)
+- `matches.test.js` - PASS individually, FAIL in suite (race conditions?)
+
+**⏳ TODO:**
+1. Check detailed errors in `users.test.js`
+2. Check detailed errors in `events.test.js`
+3. Investigate race conditions in `matches.test.js`
+4. Potentially add test isolation (beforeEach cleanup)
+5. Consider using transactions in tests
+
+**Commits made:**
+- `test: fix socket.test.js cleanup and event room parameters`
+- `test: improve test cleanup - selective deletion instead of wiping tables`
+
+### 📋 FUTURE UX/UI IMPROVEMENTS
+
+**Dashboard Page (Post-Login):**
+- [ ] Create `/dashboard` route as default landing page after login
+- [ ] Show current user information (profile summary, stats)
+- [ ] Quick access buttons to active chats (event rooms, match chats)
+- [ ] Display ongoing discussions/conversations
+- [ ] Show upcoming events user is registered for
+- [ ] Recent activity feed (new matches, messages, ratings)
+- [ ] Navigation shortcuts to key features
+
+**Event Chat Sidebar Enhancements:**
+- [ ] Add competitor number display for each user in sidebar
+- [ ] Show user nationality (flag + country code)
+- [ ] Expand user info cards in sidebar:
+  - Competition heats (already implemented)
+  - Competitor number
+  - Country/nationality
+  - User role/level
+  - Years of experience (if available in profile)
+  - Average rating (if rated)
+- [ ] Consider expandable user cards (click to see more details)
+- [ ] Add filtering options:
+  - By nationality
+  - By division/level
+  - By competitor number range
+- [ ] Improve mobile responsiveness for extended sidebar info
+
 ### ✅ Completed
 - Phase 0: Frontend mockup with all views
 - Phase 1: Backend Foundation