chore: update CI to use pnpm and minor fixes

- Update GitHub Actions release workflow to use pnpm instead of npm
- Add pnpm/action-setup@v4 for pnpm installation
- Use pnpm install --frozen-lockfile for CI builds

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.github/workflows/release.yml

@@ -52,6 +52,11 @@ jobs:
         with:
           node-version: '20'
 
+      - name: Setup pnpm
+        uses: pnpm/action-setup@v4
+        with:
+          version: 9
+
       - name: Install Linux dependencies
         if: matrix.platform == 'ubuntu-22.04'
         run: |
@@ -72,7 +77,7 @@ jobs:
           cache-all-crates: true
 
       - name: Install frontend dependencies
-        run: npm ci
+        run: pnpm install --frozen-lockfile
 
       - name: Build Tauri app
         uses: tauri-apps/tauri-action@v0