Add ComfyUIMini mobile-friendly UI integration

New features:
- ComfyUIMini container (Node.js Alpine, ~150MB) for mobile/tablet access
- Separate container architecture with shared Docker network
- Health checks on both services with proper dependency ordering
- Shared output volume for image gallery feature

Files added:
- comfyuimini/Dockerfile - Node.js 20 Alpine with tsx runtime
- comfyuimini/.dockerignore - Build context filtering

Files updated:
- docker-compose.yml - Added comfyuimini service, network, health checks
- .env.example - Added COMFYUIMINI_PORT and COMFYUIMINI_REF
- README.md - Architecture diagram, ComfyUIMini docs, updated credits

Access points:
- ComfyUI (Desktop): http://<host>:8188
- ComfyUIMini (Mobile): http://<host>:3000

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

comfyuimini/.dockerignore

@@ -0,0 +1,21 @@
+# Node.js
+node_modules/
+npm-debug.log*
+
+# Git
+.git/
+.gitignore
+
+# Documentation
+*.md
+LICENSE
+
+# Environment
+.env*
+
+# IDE
+.vscode/
+.idea/
+
+# Build artifacts (will be generated in container)
+dist/