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

routers/image.py

@@ -0,0 +1,70 @@
+"""JarvisChat routers — Image generation proxy endpoint."""
+import base64
+import logging
+
+from fastapi import APIRouter, HTTPException
+from fastapi.responses import Response
+
+from cluster import CLUSTER_NODES, request_image_generate
+
+log = logging.getLogger("caic")
+router = APIRouter()
+
+
+def _find_image_node() -> str | None:
+    for name, node in CLUSTER_NODES.items():
+        if node.get("status") == "active" and "image_gen" in node.get("capabilities", []):
+            return name
+    return None
+
+
+@router.post("/api/image/generate")
+async def generate_image(request_body: dict):
+    prompt = (request_body.get("prompt") or "").strip()
+    if not prompt:
+        raise HTTPException(status_code=400, detail="Prompt is required")
+
+    negative_prompt = request_body.get("negative_prompt", "")
+    width = min(max(request_body.get("width", 1024), 256), 2048)
+    height = min(max(request_body.get("height", 1024), 256), 2048)
+    steps = min(max(request_body.get("steps", 20), 1), 50)
+    seed = request_body.get("seed", -1)
+    model = request_body.get("model", "")
+
+    node_name = _find_image_node()
+    if not node_name:
+        raise HTTPException(status_code=503, detail="No image generation service available")
+
+    log.info("image generate via %s: %s", node_name, prompt[:60])
+
+    image_b64 = await request_image_generate(
+        node_name=node_name,
+        prompt=prompt,
+        negative_prompt=negative_prompt,
+        width=width,
+        height=height,
+        steps=steps,
+        seed=seed,
+        model=model,
+    )
+
+    if image_b64 is None:
+        raise HTTPException(status_code=504, detail="Image generation timed out or failed")
+
+    image_bytes = base64.b64decode(image_b64)
+    return Response(content=image_bytes, media_type="image/png")
+
+
+@router.get("/api/image/status")
+async def image_status():
+    nodes = []
+    for name, node in CLUSTER_NODES.items():
+        caps = node.get("capabilities", [])
+        if "image_gen" in caps:
+            nodes.append({
+                "name": name,
+                "status": node.get("status"),
+                "load": node.get("load"),
+                "last_seen": node.get("last_seen"),
+            })
+    return {"available": len(nodes) > 0, "nodes": nodes}