feat: image generation service — ComfyUI cluster integration

- POST /api/image/generate proxy endpoint (admin required)
- GET /api/image/status lists available image gen nodes
- Cluster AMQP protocol: cmd.image_generate, image_generated, image_failed
- Node agent auto-detects ComfyUI, registers image_gen capability
- ComfyUI workflow builder: CheckpointLoader → KSampler → VAEDecode → SaveImage
- Hardware probe checks ComfyUI reachability + checkpoint model list
- 27 tests covering cluster handlers, router, node agent, hardware, capabilities
- Config: CAIC_COMFYUI_BASE, CAIC_COMFYUI_TIMEOUT, comfyui_port in agent.ini
- Version bump to v1.1.0
- Documentation: ai.md, wiki/Developer-Architecture.md, current-wip.md, README.md, .env.example

docker-compose.yml

@@ -19,6 +19,8 @@ services:
       - rabbitmq_password
     environment:
       - CAIC_AMQP_SECRET_PATH=/run/secrets/rabbitmq_password
+      - CAIC_COMFYUI_BASE=${CAIC_COMFYUI_BASE:-http://192.168.50.115:8188}
+      - CAIC_COMFYUI_TIMEOUT=${CAIC_COMFYUI_TIMEOUT:-120}
     env_file: .env
     depends_on:
       qdrant:        { condition: service_started }