chore: checkpoint before lint autofix

.github/pull_request_template.md

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+## Summary
+
+- What changed:
+- Why it changed:
+
+## Test Strategy Check (Required)
+
+- [ ] I validated behavior at contract/module boundaries (not private implementation details).
+- [ ] New tests are refactor-resilient (should survive internal reorganization with identical behavior).
+- [ ] For bug fixes, I added at least one regression test at the highest stable boundary.
+- [ ] I avoided brittle assertions on internals (private helper call order, private layout, incidental log text), unless behavior-critical.
+
+## Validation Performed
+
+- [ ] Host/unit tests
+- [ ] Hardware/HIL tests (if applicable)
+- [ ] Platform profile(s) validated: `i2s` / `muse` / `squeezeamp` / N/A
+
+Commands and results:
+```bash
+# paste exact commands used
+```
+
+## Risk and Rollback
+
+- Risk level: low / medium / high
+- Potential regressions:
+- Rollback plan:
+
+## Related Docs
+
+- [ ] `documentation/TESTING_CHARTER.md` reviewed
+- [ ] `documentation/HARDWARE_TEST_MATRIX.md` reviewed (if platform impact)

.github/workflows/style-lint.yml

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+name: Style Lint
+
+on:
+  push:
+    branches:
+      - "refactoring"
+      - "main"
+      - "master-cmake"
+  pull_request:
+    branches:
+      - "refactoring"
+      - "main"
+      - "master-cmake"
+
+jobs:
+  clang-format:
+    name: clang-format
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Install clang-format
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y --no-install-recommends clang-format
+
+      - name: Check style
+        run: |
+          build-scripts/lint_style.sh check