chore: setup openapi contract gate [AC-INIT]

.gitea/workflows/pr-check.yaml

@@ -4,26 +4,49 @@ on:
   pull_request:
     branches: [ main ]
     paths:
-      - 'spec/**/openapi.provider.yaml'
-      - 'spec/**/openapi.deps.yaml'
+      - '.gitea/workflows/**'
+      - 'scripts/**'
+      - 'spec/**'
       - 'src/**'
 
 jobs:
   contract-level-check:
     runs-on: ubuntu-latest
     steps:
-      - name: Checkout code
-        uses: actions/checkout@v3
+      - name: Checkout code (no GitHub dependency)
+        shell: sh
+        run: |
+          set -eu
+
+          # Expect Gitea-provided env vars in the runner
+          : "${GITEA_SERVER_URL:?GITEA_SERVER_URL is required}"
+          : "${GITEA_REPOSITORY:?GITEA_REPOSITORY is required}"
+          : "${GITEA_SHA:?GITEA_SHA is required}"
+
+          echo "GITEA_SERVER_URL=$GITEA_SERVER_URL"
+          echo "GITEA_REPOSITORY=$GITEA_REPOSITORY"
+          echo "GITEA_SHA=$GITEA_SHA"
+
+          git clone "$GITEA_SERVER_URL/$GITEA_REPOSITORY.git" .
+          git checkout "$GITEA_SHA"
 
       - name: Run OpenAPI Contract Level Check
         env:
           # For PRs targeting main, enforce provider >= L2
           REQUIRE_PROVIDER_L2: "1"
+        shell: sh
         run: |
+          set -eu
           chmod +x scripts/check-openapi-level.sh
           ./scripts/check-openapi-level.sh
 
-      - name: YAML Lint (Optional)
+      - name: YAML Parse Check (Optional)
+        shell: sh
         run: |
-          # Simple check if yq or other linter is not available
-          find spec -name "*.yaml" -o -name "*.yml" | xargs -I {} python3 -c "import yaml, sys; yaml.safe_load(open('{}'))" || echo "YAML check skipped or failed"
+          set -eu
+          if command -v python3 >/dev/null 2>&1; then
+            python3 -c "import sys; print('python3:', sys.version.split()[0])"
+            find spec -name "*.yaml" -o -name "*.yml" | xargs -I {} python3 -c "import yaml; yaml.safe_load(open('{}'))"
+          else
+            echo "python3 not available; skip YAML parse check"
+          fi