v0.3.5 — theme system, plugin platform, sectioned Settings, tab animations

- Themes: built-in presets (Ember/Forest/Ocean/Rosé) + custom-theme editor
  (per-token color pickers, live preview, JSON export/import). src/themes.ts.
- Plugin platform: JS/ESM plugins loaded via blob-module import (CSP
  script-src blob:), Host SDK with menu / file-context / view / submit-hook
  contribution points + permission model. Backend commands to list/read/enable/
  install/remove plugins under <config>/plugins/. Example plugin + PLUGINS.md.
- Settings redesigned into a sectioned hub (General / Appearance / Plugins);
  Themes and Plugins moved in, removed from the Actions menu.
- "NEW" badge on History commits submitted < 3h ago.
- Smooth tab transitions: sliding underline + content fade on Changes/History,
  and matching fades on the view-panel and dock tab groups.
- Fix: settings close button used the default browser style.

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

src-tauri/Cargo.lock

@@ -966,7 +966,7 @@ dependencies = [
 
 [[package]]
 name = "exbyte-depot"
-version = "0.3.4"
+version = "0.3.5"
 dependencies = [
  "encoding_rs",
  "serde",