docs: reorganize documentation structure for better context efficiency

Reorganization changes:
1. Moved from root → docs/:
   - QUICKSTART.md
   - QUICK_TEST.md
   - WEBRTC_TESTING_GUIDE.md

2. Created docs/archive/ and moved archival files:
   - COMPLETED.md (completed tasks archive)
   - PHASE_1.5.md (historical phase documentation)
   - RESOURCES.md (learning resources)
   - SECURITY_AUDIT.md (security audit)
   - ADMIN_CLI.md (CLI documentation)

3. Updated all references in:
   - README.md
   - docs/CONTEXT.md
   - docs/TODO.md
   - docs/SESSION_CONTEXT.md
   - docs/DEPLOYMENT.md
   - docs/QUICK_TEST.md

Active docs/ now contains only essential files:
- SESSION_CONTEXT.md (primary for context restoration)
- TODO.md
- CONTEXT.md
- ARCHITECTURE.md
- DEPLOYMENT.md
- MONITORING.md
- QUICKSTART.md
- QUICK_TEST.md
- WEBRTC_TESTING_GUIDE.md

Benefits:
- Reduced token usage when reading docs/ for context
- Clear separation between active and archived documentation
- Better organization for future maintenance

docs/QUICK_TEST.md

@@ -0,0 +1,71 @@
+# Quick WebRTC Test Checklist
+
+## Setup (2 browser windows)
+
+**Window 1:** Login as `john@example.com` / `Dance123!`  
+**Window 2:** Login as `sarah@example.com` / `Swing456!`
+
+## Test Steps
+
+### 1. Create Match
+- [ ] User A: Go to event → Request match with User B
+- [ ] User B: Accept match
+- [ ] Both: Navigate to match chat
+
+### 2. Establish WebRTC Connection
+- [ ] User A: Click "Send video (WebRTC)"
+- [ ] User A: Select a small video file (~5-10MB)
+- [ ] User A: Click "Send video (P2P)"
+- [ ] Both: Status shows "Connecting..." → "Connected (P2P)" ✅
+
+### 3. File Transfer
+- [ ] User A: See progress bar 0% → 100%
+- [ ] User B: See "📥 Receiving: [filename]"
+- [ ] User B: File downloads automatically when complete
+- [ ] Both: Chat message appears: "📹 Video sent: [filename]"
+
+## Console Logs to Check (F12)
+
+**User A:**
+```
+📤 Sent WebRTC offer
+📤 Sent ICE candidate
+✅ DataChannel opened
+📤 Sent file metadata
+📤 Sent chunk 1/X
+✅ File transfer complete
+```
+
+**User B:**
+```
+📥 Received WebRTC offer
+✅ DataChannel received
+📥 Receiving file
+📥 Received chunk 1/X
+✅ File received and downloaded
+```
+
+## Success Criteria
+
+✅ Connection state: "Connected (P2P)" with green dot  
+✅ Transfer completes: 100% on both sides  
+✅ File downloads on receiver side  
+✅ File size matches original  
+✅ No errors in console
+
+## If Something Fails
+
+1. Check both users are in same match chat
+2. Check Socket.IO is connected (message input not disabled)
+3. Check browser console for errors
+4. Try refreshing both windows
+5. See docs/WEBRTC_TESTING_GUIDE.md for detailed troubleshooting
+
+## Start Testing
+
+```bash
+docker compose up --build
+# Then open http://localhost:8080 in two browser windows
+```
+
+🚀 **Ready to test!**