feat(mcp-image-gen): add test suite (19 tests) and Lumen profile pictures

mcp/mcp-image-gen/src/server.py

@@ -40,7 +40,9 @@ class ComfyUIClient:
 
     async def queue_prompt(self, workflow: dict) -> str:
         """Submit a workflow to ComfyUI and return the prompt_id."""
-        payload = {"prompt": workflow}
+        # Strip internal metadata keys (e.g. "_meta") — they are not ComfyUI nodes
+        clean_workflow = {k: v for k, v in workflow.items() if not k.startswith("_")}
+        payload = {"prompt": clean_workflow}
         async with httpx.AsyncClient(timeout=30.0) as client:
             resp = await client.post(f"{self.base_url}/api/prompt", json=payload)
             resp.raise_for_status()
@@ -115,7 +117,8 @@ def build_flux_workflow(
     wf["27"]["inputs"]["height"] = height
     wf["13"]["inputs"]["steps"] = steps
     wf["13"]["inputs"]["seed"] = actual_seed
-    wf["30"]["inputs"]["ckpt_name"] = model
+    # Node 32 = UNETLoader (flux1-schnell.safetensors is UNet-only, not all-in-one checkpoint)
+    wf["32"]["inputs"]["unet_name"] = model
 
     # Attach the actual seed as metadata so callers can retrieve it
     wf["_meta"] = {"actual_seed": actual_seed}