feat(history-rewrite): Enhance history rewrite process with detailed backup and validation steps

- Added a comprehensive plan for history rewrites in `docs/plans/history_rewrite.md`, including backup requirements and a checklist for destructive operations.
- Created a QA report for history-rewrite scripts in `docs/reports/qa_report.md`, summarizing tests, findings, and recommendations.
- Introduced `check_refs.sh` script to list branches and tags, saving a tarball of tag references.
- Updated `clean_history.sh` to include non-interactive mode and improved error handling for backup branch pushes.
- Enhanced `preview_removals.sh` to support JSON output format and added shallow clone detection.
- Added Bats tests for `clean_history.sh` and `validate_after_rewrite.sh` to ensure functionality and error handling.
- Implemented pre-commit hook to block commits to `data/backups/` directory.
- Improved validation script to check for backup branch existence and run pre-commit checks.
- Created temporary test scripts for validating `clean_history.sh` and `validate_after_rewrite.sh` functionality.

.pre-commit-config.yaml

@@ -50,6 +50,13 @@ repos:
         pass_filenames: false
         verbose: true
         always_run: true
+      - id: block-data-backups-commit
+        name: Prevent committing data/backups files
+        entry: bash scripts/pre-commit-hooks/block-data-backups-commit.sh
+        language: system
+        pass_filenames: false
+        verbose: true
+        always_run: true
 
       # === MANUAL/CI-ONLY HOOKS ===
       # These are slow and should only run on-demand or in CI