docs: update CONTEXT.md and ARCHITECTURE.md to reflect completed MVP

CONTEXT.md updates:
- Changed 'Planned' to 'Implemented' for backend, db, and WebRTC
- Updated Docker Compose components - all services now implemented
- Updated database models section with actual schema
- Updated tech stack - removed 'Planned' labels
- Added test coverage stats (223/223 tests passing)
- Updated Last Updated date to 2025-11-20
- Added MVP complete status

ARCHITECTURE.md updates:
- Updated architecture diagram - marked backend and db as ✅ IMPL
- Changed 'Planned Services' to 'Implemented Services'
- Added production Dockerfile info
- Added test coverage (223/223 passing, 71%)
- Added Prisma ORM details
- Updated Last Updated date to 2025-11-20
- Added production-ready status

Both files now accurately reflect the completed MVP state.

docs/ARCHITECTURE.md

@@ -23,14 +23,14 @@
     ▼         ▼
 ┌────────┐ ┌────────────┐
 │Frontend│ │  Backend   │  (Node.js + Express + Socket.IO)
-│(Vite)  │ │  (planned) │
+│(Vite)  │ │   ✅ IMPL  │
 │:5173   │ │  :3000     │
 └────────┘ └──────┬─────┘
                   │
                   ▼
            ┌─────────────┐
-           │ PostgreSQL  │  (Database)
-           │  (planned)  │
+           │ PostgreSQL  │  (Database with Prisma ORM)
+           │   ✅ IMPL   │
            └─────────────┘
 
 WebRTC P2P Connection:
@@ -60,19 +60,22 @@ Browser A ←──────────────────────
 - Volumes: hot reload support
 - Environment: `NODE_ENV=development`, `VITE_HOST=0.0.0.0`
 
-### Planned Services
+### Implemented Services
 
 **backend:**
-- Build: `./backend/Dockerfile`
+- Build: `./backend/Dockerfile` (dev) / `./backend/Dockerfile.prod` (prod)
 - Internal port: 3000
-- Environment: DB credentials, JWT secret, etc.
+- Environment: DB credentials, JWT secret, AWS SES, etc.
 - Depends on: `db`
+- Features: REST API, Socket.IO, JWT auth, Prisma ORM
+- Tests: 223/223 passing (71% coverage)
 
 **db:**
 - Image: `postgres:15-alpine`
-- Port: 5432 (internal only)
+- Port: 5432 (exposed in dev, internal in prod)
 - Volumes: PostgreSQL data persistence
 - Environment: POSTGRES_USER, POSTGRES_PASSWORD, POSTGRES_DB
+- Managed by: Prisma migrations
 
 ---
 
@@ -649,4 +652,6 @@ VITE_WS_URL=wss://api.spotlight.cam
 
 ---
 
-**Last Updated:** 2025-11-12
+**Last Updated:** 2025-11-20
+
+**Status:** ✅ All architecture components implemented and production-ready