ci: install only changed charts and skip kind when nothing installable

.github/workflows/test.yaml

@@ -29,11 +29,16 @@ jobs:
 
       - name: Run chart-testing (list-changed)
         id: list-changed
+        # paperlessngx-ftp-bridge is excluded from install (see below), so a PR
+        # touching only that chart needs lint but no kind cluster.
         run: |
           changed=$(ct list-changed --target-branch main)
           if [[ -n "$changed" ]]; then
             echo "changed=true" >> $GITHUB_OUTPUT
           fi
+          if [[ -n "$changed" ]] && grep -qvx 'charts/paperlessngx-ftp-bridge' <<<"$changed"; then
+            echo "installable=true" >> $GITHUB_OUTPUT
+          fi
 
       - name: Run chart-testing (lint)
         if: steps.list-changed.outputs.changed == 'true'
@@ -43,16 +48,20 @@ jobs:
             --target-branch main
 
       - name: Add chart repositories
-        if: steps.list-changed.outputs.changed == 'true'
+        if: steps.list-changed.outputs.installable == 'true'
         run: helm repo add taskmedia https://helm.task.media
 
       - name: Create kind cluster
         uses: helm/kind-action@v1.13.0
-        if: steps.list-changed.outputs.changed == 'true'
+        if: steps.list-changed.outputs.installable == 'true'
 
       - name: Run chart-testing (install)
-        if: steps.list-changed.outputs.changed == 'true'
+        if: steps.list-changed.outputs.installable == 'true'
         # paperlessngx-ftp-bridge is excluded: its Service is a hardcoded
         # LoadBalancer (kind assigns no external IP, so `--wait` would hang)
         # and its image is built in the bridge repo, not here.
-        run: ct install --all --chart-dirs charts --excluded-charts paperlessngx-ftp-bridge
+        run: |
+          ct install \
+            --target-branch main \
+            --chart-dirs charts \
+            --excluded-charts paperlessngx-ftp-bridge