feat: add browser support for provider OAuth in Docker

Docker changes:
- Install Node.js and npm (for Claude CLI)
- Install Firefox ESR for browser-based OAuth
- Install X11 libraries for display forwarding
- Add 'setup' service with display access

Usage:
  xhost +local:docker
  docker-compose run --rm setup
  smarttools providers install

The 'setup' service has DISPLAY and X11 socket access, so browser-based
OAuth flows (Claude, Codex, Gemini, OpenCode) can work inside Docker.

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

Co-Authored-By: Claude Opus 4.5 <[email protected]>

Dockerfile

@@ -11,6 +11,15 @@ LABEL description="SmartTools - Personal AI-powered CLI command builder"
 RUN apt-get update && apt-get install -y --no-install-recommends \
     git \
     curl \
+    # Node.js for Claude CLI
+    nodejs \
+    npm \
+    # Browser for OAuth authentication
+    firefox-esr \
+    # X11 libraries for display
+    libx11-6 \
+    libxext6 \
+    libxrender1 \
     && rm -rf /var/lib/apt/lists/*
 
 # Set working directory