feat: tooltips, two-column timer, font selector, tray behavior, icons, readme

- Custom tooltip directive (WCAG AAA) on every button in the app
- Two-column timer layout with sticky hero and recent entries sidebar
- Timer font selector with 16 monospace Google Fonts and live preview
- UI font selector with 15+ Google Fonts
- Close-to-tray and minimize-to-tray settings
- New app icons (no-glow variants), platform icon set
- Mini timer pop-out window
- Favorites strip with drag-reorder and inline actions
- Comprehensive README with feature documentation
- Remove tracked files that belong in gitignore

tsconfig.json

@@ -15,6 +15,7 @@
     "noUnusedLocals": true,
     "noUnusedParameters": true,
     "noFallthroughCasesInSwitch": true,
+    "baseUrl": ".",
     "paths": {
       "@/*": ["./src/*"]
     }