* refactor: align VS Code update checks with web runtime parity
- VS Code now uses file-based installId (shared with web server)
- Accepts platform/arch from webview for consistent behavior
- Usage data collection now matches web implementation
* feat: Add opt-out setting for anonymous usage reporting in Appearance
- Add privacy control in Appearance settings to opt-out of anonymous usage reports
- Usage data includes only app version, platform, and runtime - no personal data or code collected
- Setting persists across all runtimes and controls the reportUsage parameter in update checks