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
- README with feature documentation
- Remove tracked files that belong in gitignore

src/utils/markdown.ts

@@ -1,4 +1,5 @@
 import { marked } from 'marked'
+import DOMPurify from 'dompurify'
 
 marked.setOptions({
   breaks: true,
@@ -7,7 +8,8 @@ marked.setOptions({
 
 export function renderMarkdown(text: string): string {
   if (!text) return ''
-  return marked.parseInline(text) as string
+  const raw = marked.parseInline(text) as string
+  return DOMPurify.sanitize(raw, { ALLOWED_TAGS: ['strong', 'em', 'code', 'a', 'br'], ALLOWED_ATTR: ['href', 'target', 'rel'] })
 }
 
 export function stripMarkdown(text: string): string {