feat(mcp-image-gen): scaffold ComfyUI-backed image generation MCP server

- FastMCP server with 4 tools: generate_image, list_available_models,
  get_generation_status, get_output_directory
- ComfyUI REST API client (httpx) polling lifecycle
- FLUX.1-schnell workflow JSON template
- Dual output: TextContent (path + seed) + ImageContent (base64 PNG)
- 14 passing pytest tests with respx HTTP mocking
- ROCm/AMD RX 7900 XTX optimized setup in README
- Ollama Linux migration path documented (future)

mcp/mcp-image-gen/run.sh

@@ -0,0 +1,13 @@
+#!/usr/bin/env bash
+# Run mcp-image-gen MCP server
+set -euo pipefail
+
+BASEDIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+export PATH="$HOME/.local/bin:$PATH"
+
+# Create output dir if it doesn't exist
+OUTPUT_DIR="${IMAGE_OUTPUT_DIR:-$HOME/Pictures/mcp-generated}"
+mkdir -p "$OUTPUT_DIR"
+
+cd "$BASEDIR"
+exec uv run src/server.py