Initial implementation of UniFi MCP Light server

Implements Hybrid MCP Light pattern with:
- 4 specific tools: list_clients, list_devices, get_system_info, get_network_health
- Meta tools: tool_index, api_call (raw API pass-through)
- API documentation resource at unifi://api-reference
- Starlette wrapper with /health endpoint
- Write protection (UNIFI_ALLOW_WRITES env var)
- UniFi OS auto-detection (proxy vs direct paths)
- Docker multi-stage build
- Gitea CI workflow

Closes #1, #2, #3, #4, #5, #7

docker-compose.yml

@@ -0,0 +1,24 @@
+services:
+  unifi-mcp-light:
+    build: .
+    image: gitea.ext.ben.io/b3nw/unifi-mcp-light:latest
+    container_name: unifi-mcp-light
+    restart: unless-stopped
+    ports:
+      - "${PORT:-8100}:8000"
+    environment:
+      - UNIFI_HOST=${UNIFI_HOST}
+      - UNIFI_USERNAME=${UNIFI_USERNAME}
+      - UNIFI_PASSWORD=${UNIFI_PASSWORD}
+      - UNIFI_PORT=${UNIFI_PORT:-443}
+      - UNIFI_SITE=${UNIFI_SITE:-default}
+      - UNIFI_VERIFY_SSL=${UNIFI_VERIFY_SSL:-false}
+      - UNIFI_ALLOW_WRITES=${UNIFI_ALLOW_WRITES:-false}
+    env_file:
+      - .env
+    healthcheck:
+      test: ["CMD", "python", "-c", "import urllib.request; urllib.request.urlopen('http://localhost:8000/health')"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+      start_period: 10s