feat(android): generate launcher icons from zeavis-logo.svg during CI build

- Add scripts/generate-icons.js using sharp to convert SVG to PNG
  at all Android density buckets (mdpi 48→xxxhdpi 192)
- Add sharp as devDependency
- Update CI workflow to run icon generation after tauri android init
- Replaces Tauri's default icons with ZeaVis Edu logo

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

.github/workflows/android.yml

@@ -136,7 +136,11 @@ jobs:
           rm -rf gen/android
           bun tauri android init
 
-      - name: Patch AndroidManifest (CAMERA permission)
+      - name: Generate Android launcher icons from SVG logo
+        working-directory: apps/tauri
+        run: bun run scripts/generate-icons.js
+
+      - name: Patch AndroidManifest (CAMERA permission + deep link)
         working-directory: apps/tauri
         run: bash scripts/patch-android-manifest.sh