Initial commit: Multi-service AI agent system

- Frontend: Vite + React + TypeScript chat interface
- Backend: FastAPI gateway with LangGraph routing
- Knowledge Service: ChromaDB RAG with Gitea scraper
- LangGraph Service: Multi-agent orchestration
- Airflow: Scheduled Gitea ingestion DAG
- Documentation: Complete plan and implementation guides

Architecture:
- Modular Docker Compose per service
- External ai-mesh network for communication
- Fast rebuilds with /app/packages pattern
- Intelligent agent routing (no hardcoded keywords)

Services:
- Frontend (5173): React chat UI
- Chat Gateway (8000): FastAPI entry point
- LangGraph (8090): Agent orchestration
- Knowledge (8080): ChromaDB RAG
- Airflow (8081): Scheduled ingestion
- PostgreSQL (5432): Chat history

Excludes: node_modules, .venv, chroma_db, logs, .env files
Includes: All source code, configs, docs, docker files

docker-compose.yml

@@ -0,0 +1,41 @@
+services:
+  db:
+    image: postgres:15-alpine
+    environment:
+      POSTGRES_USER: sam
+      POSTGRES_PASSWORD: sam4jo 
+      POSTGRES_DB: chat_demo
+    ports:
+      - "5432:5432"
+    volumes:
+      - postgres_data:/var/lib/postgresql/data
+    networks:
+      - ai-mesh
+  backend:
+    build: ./backend
+    ports:
+      - "8000:8000"
+    environment:
+      DATABASE_URL: postgresql://sam:sam4jo@db:5432/chat_demo
+    volumes:
+      - ./backend:/app
+    depends_on:
+      - db
+    networks:
+      - ai-mesh
+  frontend:
+    build: ./frontend
+    ports:
+      - "5173:5173"
+    volumes:
+      - ./frontend:/app
+      - /app/node_modules
+    environment:
+      - CHOKIDAR_USEPOLLING=true
+    networks:
+      - ai-mesh
+volumes:
+  postgres_data:
+networks:
+      ai-mesh:
+        external: true