ci: Add UI building to build and test workflow

Add UI building to the workflow, to automatically assess the
buildability of the UI codebase after Renovate Bot 's suggested UI
dependency updates.

Signed-off-by: Jyrki Keisala <[email protected]>

Author: Etsija

Diff for: .github/workflows/build-and-test.yml

@@ -34,6 +34,38 @@ jobs:
     - name: Build all classes
       run: ./gradlew --stacktrace classes
 
+  build-ui:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Install Node
+      uses: actions/setup-node@v4
+      with:
+        node-version: 20
+
+    - uses: pnpm/action-setup@v3
+      name: Install pnpm
+      with:
+        version: 8
+
+    - name: Get pnpm store directory
+      shell: bash
+      run: |
+        echo "STORE_PATH=$(pnpm store path --silent)" >> $GITHUB_ENV
+
+    - uses: actions/cache@v4
+      name: Setup pnpm cache
+      with:
+        path: ${{ env.STORE_PATH }}
+        key: ${{ runner.os }}-pnpm-store-${{ hashFiles('**/pnpm-lock.yaml') }}
+        restore-keys: |
+          ${{ runner.os }}-pnpm-store-
+
+    - name: Install UI dependencies
+      run: |
+        cd ui
+        pnpm install
+        pnpm build
+
   test:
     needs: build
     runs-on: ubuntu-latest