docs: update documentation for Phase 2.5 completion and Phase 3 start

Update README.md:
- Add landing page to features
- Update test coverage section (43% backend, 116 tests passing)
- Add WebRTC tests information (7 tests passing)
- Update project structure (HomePage, hooks, utils, tests)
- Add STUN servers to WebRTC features
- Remove STUN/TURN and server upload fallback from Next Up
- Update roadmap to Phase 3 in progress
- Update test flow with landing page
- Update progress to ~80%

Update SESSION_CONTEXT.md:
- Current phase: Phase 3 (MVP Finalization) in progress
- Add landing page and WebRTC tests to What Works Now
- Update What's Missing (remove STUN, add coverage improvement)
- Add HomePage to routes and key files
- Add useWebRTC, webrtcDetection, test files to key files
- Update socket.js description with WebRTC signaling
- Update final status with all completed phases
- Update progress and date

README.md

@@ -50,18 +50,24 @@ Web application (PWA) for the dance community enabling matchmaking, chat, and vi
 - ✅ **E2E Encryption** - DTLS encryption (native WebRTC)
 - ✅ **Auto Download** - automatic file download on receiver side
 
+**Landing Page:**
+- ✅ **Homepage** - professional landing page with hero section, features showcase, and CTAs
+- ✅ **Public Access** - accessible to non-logged users with links to register/login
+- ✅ **Responsive Design** - mobile-friendly with gradient backgrounds
+
 **Backend & Infrastructure:**
 - ✅ **PostgreSQL Database** - 7 tables with relations (Prisma ORM)
 - ✅ **RESTful API** - Express.js backend with validation
 - ✅ **WebSocket** - Socket.IO for real-time communication
 - ✅ **Docker Compose** - full orchestration (nginx, frontend, backend, PostgreSQL)
-- ✅ **Test Coverage** - 81%+ coverage (Jest + Supertest)
+- ✅ **Test Coverage** - comprehensive test suite for WebRTC, Auth, Events, Matches
+- ✅ **WebRTC Tests** - full Socket.IO signaling and detection tests (7 tests passing)
 
 ### 🔜 Next Up
 
-- ⏳ **STUN/TURN Servers** - WebRTC NAT traversal for production
-- ⏳ **Server Upload Fallback** - alternative when WebRTC blocked
 - ⏳ **Competition Heats** - complete UI integration and real-time updates
+- ⏳ **PWA Features** - manifest, service worker, offline support
+- ⏳ **Security Hardening** - CORS, CSRF, Helmet.js, CSP
 
 ## 🛠️ Tech Stack
 
@@ -104,9 +110,11 @@ spotlightcam/
 │   │   ├── components/        # React components
 │   │   │   ├── common/        # Shared components, PasswordStrength, VerificationBanner
 │   │   │   ├── chat/          # Chat components
-│   │   │   ├── video/         # WebRTC video transfer (mockup)
-│   │   │   └── layout/        # Navbar, Layout
+│   │   │   ├── video/         # WebRTC components (WebRTCWarning)
+│   │   │   ├── layout/        # Navbar, Layout
+│   │   │   └── __tests__/     # Component tests (WebRTCWarning)
 │   │   ├── pages/             # Application pages
+│   │   │   ├── HomePage.jsx             # Landing page with hero & features
 │   │   │   ├── LoginPage.jsx
 │   │   │   ├── RegisterPage.jsx         # Two-step registration with WSDC lookup
 │   │   │   ├── VerifyEmailPage.jsx      # Email verification (link + PIN)
@@ -116,9 +124,12 @@ spotlightcam/
 │   │   │   ├── PublicProfilePage.jsx    # View other user's profile
 │   │   │   ├── EventsPage.jsx           # Event list with real API
 │   │   │   ├── EventChatPage.jsx        # Real-time event chat
-│   │   │   ├── MatchChatPage.jsx        # Private chat + WebRTC mockup
+│   │   │   ├── MatchChatPage.jsx        # Private chat + WebRTC P2P transfer
 │   │   │   ├── RatePartnerPage.jsx      # Rate partner after collaboration
 │   │   │   └── HistoryPage.jsx          # Match history
+│   │   ├── hooks/             # Custom hooks (useWebRTC)
+│   │   ├── utils/             # Utilities (webrtcDetection)
+│   │   │   └── __tests__/     # Utility tests (webrtcDetection)
 │   │   ├── contexts/          # AuthContext (JWT integration)
 │   │   ├── services/          # API client, Socket.IO client
 │   │   ├── data/              # Static data (countries list)
@@ -131,9 +142,14 @@ spotlightcam/
 │   │   ├── controllers/       # Auth, users, events, WSDC
 │   │   ├── middleware/        # Auth, validation, error handling
 │   │   ├── routes/            # API routes
-│   │   ├── socket/            # Socket.IO server (event/match rooms)
+│   │   ├── socket/            # Socket.IO server (event/match rooms, WebRTC signaling)
 │   │   ├── utils/             # Auth utils, DB, email service (AWS SES)
-│   │   └── __tests__/         # Jest unit tests (81%+ coverage)
+│   │   └── __tests__/         # Jest unit tests
+│   │   │   ├── socket-webrtc.test.js  # WebRTC signaling tests (7 tests)
+│   │   │   ├── auth.test.js           # Authentication tests
+│   │   │   ├── events.test.js         # Events API tests
+│   │   │   ├── matches.test.js        # Matches API tests
+│   │   │   └── ...                    # Other test suites
 │   ├── prisma/
 │   │   ├── schema.prisma      # Database schema (7 tables)
 │   │   ├── migrations/        # Database migrations
@@ -278,45 +294,52 @@ Adds:
 
 ### Test Flow:
 
-1. **Registration with WSDC** (http://localhost:8080/register)
+1. **Landing Page** (http://localhost:8080/)
+   - View professional landing page with hero section
+   - Explore features showcase and how-it-works section
+   - Click "Get Started" to register or "Sign in" to login
+
+2. **Registration with WSDC** (http://localhost:8080/register)
    - Optional: provide WSDC ID (e.g., 12345) for auto-fill
    - Complete registration form
    - You'll receive verification email (check AWS SES sandbox)
 
-2. **Email Verification** (http://localhost:8080/verify-email)
+3. **Email Verification** (http://localhost:8080/verify-email)
    - Click link from email OR enter 6-digit PIN code
    - Email will be verified
 
-3. **Login** (http://localhost:8080/login)
+4. **Login** (http://localhost:8080/login)
    - Email: john@example.com
    - Password: password123
 
-4. **Profile Editing** (http://localhost:8080/profile)
+5. **Profile Editing** (http://localhost:8080/profile)
    - Add social media links (Instagram, YouTube, etc.)
    - Select country from list of 195 countries
    - Enter city
    - Edit WSDC ID, first name, last name
 
-5. **Event Selection** (http://localhost:8080/events)
+6. **Event Selection** (http://localhost:8080/events)
    - View event list (joined events appear at top)
    - Select event (e.g., "Warsaw Dance Festival 2025")
    - Click "Join chat" or "Open chat" (if already joined)
 
-6. **Event Chat**
+7. **Event Chat**
    - Real-time chat with Socket.IO
    - Active users list on the right side
    - Click "+" icon next to user to connect
    - You'll be redirected to private 1:1 chat
 
-7. **1:1 Chat - WebRTC P2P File Transfer** 🔥
+8. **1:1 Chat - WebRTC P2P File Transfer** 🔥
    - See partner's profile at top (click username to view public profile)
    - WebRTC connection status (disconnected/connecting/connected)
    - **Sending video via WebRTC:**
      - Click "Send video (WebRTC)"
      - Select video file from disk
-     - Real P2P transfer via RTCDataChannel (supports files up to 700MB+)
-     - See real-time progress bar
+     - Real P2P transfer via RTCDataChannel with STUN servers for NAT traversal
+     - Supports files up to 700MB+ tested successfully
+     - See real-time progress bar (16KB chunking)
      - Receiver automatically downloads the file
+     - End-to-end encryption via DTLS (native WebRTC)
    - **WebRTC Detection:**
      - Automatic detection if WebRTC is blocked
      - User-friendly warning with fix suggestions
@@ -326,18 +349,18 @@ Adds:
      - Paste video URL (Google Drive, Dropbox, etc.)
      - Alternative when WebRTC blocked (Opera, VPNs, privacy settings)
 
-8. **Rate Partner** (coming soon - Matches & Ratings API)
+9. **Rate Partner**
    - Click "Finish and rate"
    - Select rating (1-5 stars)
    - Add comment
    - Mark if you want to collaborate again
 
-9. **Collaboration History** (http://localhost:8080/history)
-   - See list of matches
-   - See received ratings
-   - See statistics
+10. **Collaboration History** (http://localhost:8080/history)
+    - See list of matches
+    - See received ratings
+    - See statistics
 
-10. **Public Profiles**
+11. **Public Profiles**
     - Click on another user's username
     - View profile: avatar, location, social media, statistics
 
@@ -387,15 +410,29 @@ Adds:
 
 ## 📊 Test Coverage
 
-**Backend: 81%+ coverage**
-- Auth controllers: 78%
-- Socket.IO module: 89%
-- Jest + Supertest
+**Backend: ~43% overall coverage** (116 tests passing)
+- **WebRTC Signaling**: 7/7 tests passing (offer/answer/ICE relay, authorization)
+- **Auth Controllers**: 82.9% coverage
+- **Events API**: Comprehensive tests
+- **Matches API**: Full CRUD tests
+- **Socket.IO**: 42.4% coverage (WebRTC + chat)
+
+**Frontend: Test files ready** (requires test runner setup)
+- WebRTC detection utility tests
+- WebRTC warning component tests
+
+**Coverage gaps** (priority areas):
+- Routes: events.js (8.98%), matches.js (8.22%), users.js (43%)
+- Controllers: user.js (8.19%)
+- Utils: sanitize.js (31.81%)
 
 ```bash
-# Run tests
+# Run all backend tests
 docker compose exec backend npm test
 
+# Run specific test suite
+docker compose exec backend npm test -- socket-webrtc.test.js
+
 # Coverage report
 docker compose exec backend npm run test:coverage
 ```
@@ -434,17 +471,22 @@ docker compose exec backend npm run test:coverage
 ### ✅ Phase 2.5: WebRTC P2P File Transfer (COMPLETED)
 - WebRTC signaling (SDP/ICE exchange via Socket.IO)
 - P2P file transfer via RTCDataChannel (16KB chunking)
+- STUN servers for NAT traversal (production-ready)
 - WebRTC capability detection (browser/network compatibility)
 - User-friendly fallback UX when WebRTC blocked
 - Tested up to 700MB file transfers
 - E2E encryption (DTLS)
+- Comprehensive test suite (7 backend tests passing)
+- Professional landing page with hero section
 
-### ⏳ Phase 3: MVP Finalization (PLANNED)
-- Security hardening
-- Integration & E2E tests
-- PWA features (manifest, service worker)
-- Production deployment
-- Monitoring & logging
+### ⏳ Phase 3: MVP Finalization (IN PROGRESS)
+- ✅ Landing page (completed)
+- ✅ WebRTC tests (completed)
+- ⏳ Security hardening (CORS, CSRF, Helmet.js, CSP)
+- ⏳ Integration & E2E tests
+- ⏳ PWA features (manifest, service worker)
+- ⏳ Production deployment
+- ⏳ Monitoring & logging
 
 ### ⏳ Phase 4: Extensions (FUTURE)
 - User badges & trust system
@@ -489,6 +531,6 @@ TBD
 
 ---
 
-**Current Status:** Phase 2.5 (WebRTC) ✅ Completed | Phase 3 (MVP) ⏳ Next | Progress: ~78% overall
+**Current Status:** Phase 2.5 (WebRTC) ✅ Completed | Phase 3 (MVP) ⏳ In Progress | Progress: ~80% overall
 
 **Last Updated:** 2025-11-15