Add desktop tray widget + installer wizard

- Desktop widget (Python/pystray): system tray icon showing 5h usage as
  circular progress bar with Claude starburst logo, 10-step green-to-red
  color scale, right-click menu with usage stats and configuration
- Shared cache: both widget and CLI statusline read/write the same
  /tmp/claude_usage.json — only one fetcher needs to run
- Installer wizard (install_wizard.py): interactive cross-platform setup
  with component selection, session key prompt, cron/autostart config
- OS wrappers: install.sh (Linux/macOS) and install.ps1 (Windows) find
  Python 3.9+ and launch the wizard
- README with topology diagram, usage docs, and configuration reference

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

package.json

@@ -1,7 +1,7 @@
 {
   "name": "claude-statusline",
-  "version": "0.1.0",
-  "description": "Standalone Claude Code statusline for headless Linux servers",
+  "version": "0.2.0",
+  "description": "Claude Code usage monitoring — CLI statusline (Node.js) + desktop tray widget (Python)",
   "main": "statusline.js",
   "scripts": {
     "statusline": "node statusline.js",