Show app version in sidebar, make the sidebar collapsible, and add a Light/Dark/Auto theme switch

- Expose the AeroFetch version over IPC (app:version → app.getVersion); the
  sidebar brand now shows "v<version>" beneath the name.
- Sidebar can collapse to a 60px icon-only rail via a toggle button; nav items
  and the theme control fall back to icon + tooltip when collapsed. The state is
  persisted in localStorage so it survives restarts. Hint gains left/right
  placements for the collapsed-rail tooltips.
- Replace the binary dark-mode Switch with an explicit 3-way Light / Dark / Auto
  segmented control (Auto follows the OS). Collapsed, it becomes a single button
  that cycles the three modes.
- Bump version to 0.3.2.

Verified in the browser UI preview: version label, collapse/expand, dark mode,
and the theme switch all render correctly with no console errors.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "aerofetch",
-  "version": "0.3.1",
+  "version": "0.3.2",
   "description": "A yt-dlp frontend for Windows",
   "main": "./out/main/index.js",
   "author": "AeroFetch",