fix(ci:testdriver): conditionally run frontend tests based on file changes (#4064)

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

.github/config/.files.yaml

@@ -30,3 +30,9 @@ project: &project
   - frontend/**
   - docker/**
   - testing/**
+
+frontend: &frontend
+  - frontend/**
+  - .github/workflows/testdriver.yml
+  - testing/**
+  - docker/**

.github/workflows/testdriver.yml

@@ -116,8 +116,25 @@ jobs:
             docker-compose up -d
           EOF
 
+  files-changed:
+    if: always()
+    name: detect what files changed
+    runs-on: ubuntu-latest
+    timeout-minutes: 3
+    outputs:
+      frontend: ${{ steps.changes.outputs.frontend }}
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+
+      - name: Check for file changes
+        uses: dorny/paths-filter@de90cc6fb38fc0963ad72b210f1f284cd68cea36 # v3.0.2
+        id: changes
+        with:
+          filters: ".github/config/.files.yaml"
+
   test:
-    needs: deploy
+    if: needs.files-changed.outputs.frontend == 'true'
+    needs: [deploy, files-changed]
     runs-on: ubuntu-latest
 
     steps:
@@ -132,12 +149,14 @@ jobs:
         uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4.4.0
         with:
           cache: 'npm'
+          cache-dependency-path: frontend/package-lock.json
 
       - name: Run TestDriver.ai
         uses: testdriverai/action@f0d0f45fdd684db628baa843fe9313f3ca3a8aa8 #1.1.3
         with:
           key: ${{secrets.TESTDRIVER_API_KEY}}
           prerun: |
+            cd frontend
             npm install
             npm run build
             npm install dashcam-chrome --save
@@ -167,6 +186,7 @@ jobs:
           sudo chmod 600 ../private.key
 
       - name: Cleanup deployment
+        if: always()
         run: |
           ssh -i ../private.key -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null ${{ secrets.VPS_USERNAME }}@${{ secrets.VPS_HOST }} << EOF
             cd /stirling/test-${{ github.sha }}
@@ -174,3 +194,4 @@ jobs:
             cd /stirling
             rm -rf test-${{ github.sha }}
           EOF
+        continue-on-error: true # Ensure cleanup runs even if previous steps fail