Completely isolate the original project's .github/

.github-orig/workflows/checks.yml

@@ -0,0 +1,74 @@
+name: Perform checks
+
+on:
+  pull_request:
+    branches: [ master ]
+    paths:
+      - '**'
+      - '!.github/**'
+      - '!*.yml'
+      - '!*.config'
+      - '!*.md'
+      - '.github/workflows/*.yml'
+
+permissions:
+  pull-requests: write
+  checks: write
+
+concurrency:
+  group: pr-checks-${{ github.event.number }}
+  cancel-in-progress: true
+
+jobs:
+  format:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - uses: actions/setup-dotnet@v4
+        with:
+          global-json-file: global.json
+
+      - name: Overwrite csc problem matcher
+        run: echo "::add-matcher::.github/csc.json"
+
+      - run: dotnet restore
+
+      - name: Print dotnet format version
+        run: dotnet format --version
+
+      - name: Run dotnet format whitespace
+        run: |
+          dotnet format whitespace --verify-no-changes --report ./whitespace-report.json -v d
+
+      # For some unknown reason this step sometimes fails with exit code 139 (segfault?),
+      # so in that case we'll try again (3 tries max).
+      - name: Run dotnet format style
+        uses: TSRBerry/unstable-commands@v1
+        with:
+          commands: dotnet format style --severity info --verify-no-changes --report ./style-report.json -v d
+          timeout-minutes: 5
+          retry-codes: 139
+
+      # For some unknown reason this step sometimes fails with exit code 139 (segfault?),
+      # so in that case we'll try again (3 tries max).
+      - name: Run dotnet format analyzers
+        uses: TSRBerry/unstable-commands@v1
+        with:
+          commands: dotnet format analyzers --severity info --verify-no-changes --report ./analyzers-report.json -v d
+          timeout-minutes: 5
+          retry-codes: 139
+
+      - name: Upload report
+        if: failure()
+        uses: actions/upload-artifact@v4
+        with:
+          name: dotnet-format
+          path: ./*-report.json
+
+  pr_build:
+    uses: ./.github/workflows/build.yml
+    needs: format
+    secrets: inherit