[CHORE](ci) Add all-Python-checks gate, resolve Build job-name collision

.github/workflows/check-python-code.yaml

@@ -92,3 +92,18 @@ jobs:
 
       - name: Run make check
         run: make check
+
+  # Single stable check-run name for the whole matrix, so a required-status-
+  # check rule never has to track individual Python-version cells. Add or
+  # drop a cell above and this job's name still covers it.
+  all-python-checks-pass:
+    name: All Python checks pass
+    needs: [check]
+    if: always()
+    runs-on: ubuntu-slim
+    permissions: {}
+
+    steps:
+      - uses: lowlydba/are-we-good@f506ed6324f55ec5e4ff5d92204a72c7f1c2b4f8 # v1.0.5
+        with:
+          jobs: ${{ toJSON(needs) }}

.github/workflows/schema-pr-preview.yml

@@ -23,7 +23,7 @@ jobs:
         run: |
           echo "::warning title=Staging deploy not supported for fork PRs::Staging previews are only available for PRs from branches within this repository, not forks. Please open your PR from a branch in OvertureMaps/schema instead."
   build:
-    name: Build
+    name: Build preview
     if: github.event.pull_request.head.repo.full_name == github.repository
     runs-on: ubuntu-latest
     needs: check-fork

.github/workflows/test-schema.yaml

@@ -9,12 +9,19 @@ on:
       - 'schema/**'
       - 'examples/**'
       - 'counterexamples/**'
+  pull_request:
+    paths:
+      - 'schema/**'
+      - 'examples/**'
+      - 'counterexamples/**'
 
 permissions:
   contents: read
 
 concurrency:
-  group: ${{ github.workflow }}-${{ github.ref }}
+  # push never fires for fork PRs, so pull_request is the only trigger a
+  # required check can rely on from external contributors.
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
   cancel-in-progress: true
 
 jobs: