ci: add build verification step before running tests

- Add rust-build job that compiles the full Rust workspace before tests run
- Add TypeScript type-check for the dashboard using tsc --noEmit
- rust-tests job now depends on rust-build to catch compile errors early

.github/workflows/ci.yml

@@ -75,10 +75,62 @@ jobs:
           bandit-report.json
           safety-report.json
 
+  # Build Verification — ensure the Rust workspace compiles cleanly before running tests.
+  # Catches type errors, missing imports, and dependency resolution issues early.
+  rust-build:
+    name: Rust Build Check
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout code
+      uses: actions/checkout@v4
+
+    - name: Install Tauri / GTK / serial system dev libraries
+      run: |
+        sudo apt-get update
+        sudo apt-get install -y --no-install-recommends \
+          libglib2.0-dev \
+          libgtk-3-dev \
+          libsoup-3.0-dev \
+          libjavascriptcoregtk-4.1-dev \
+          libwebkit2gtk-4.1-dev \
+          libayatana-appindicator3-dev \
+          librsvg2-dev \
+          libxdo-dev \
+          libudev-dev \
+          libdbus-1-dev \
+          libssl-dev \
+          pkg-config
+
+    - name: Install Rust toolchain
+      uses: dtolnay/rust-toolchain@stable
+
+    - name: Cache cargo
+      uses: actions/cache@v4
+      with:
+        path: |
+          ~/.cargo/registry
+          ~/.cargo/git
+          v2/target
+        key: ${{ runner.os }}-cargo-build-${{ hashFiles('v2/Cargo.lock') }}
+        restore-keys: |
+          ${{ runner.os }}-cargo-build-
+
+    - name: Build Rust workspace
+      working-directory: v2
+      run: cargo build --workspace --no-default-features
+
+    - name: TypeScript type-check (dashboard)
+      if: success()
+      run: |
+        cd ${{ github.workspace }}/dashboard
+        npm ci
+        npx tsc --noEmit
+
   # Rust Workspace Tests
   rust-tests:
     name: Rust Workspace Tests
     runs-on: ubuntu-latest
+    needs: [rust-build]
     steps:
     - name: Checkout code
       uses: actions/checkout@v4