chore: comprehensive repo health - remove test artifacts and merge cleanup

- Remove config/test_accounts.json (contains private keys)
- Enhanced .gitignore: test_*.py, demo_*.py, temp_*.py patterns
- Added root-level internal doc patterns (RELEASE_STRATEGY_SUMMARY, etc)
- Deleted merged branches: chore/repo-hardening, feature/visual-refinement-v1.1.2

Branch health:
- main: current, up-to-date (commit e97b7c3)
- Deprecated remote branches remain for archival reference only

Repository now contains:
- 134 tracked files (down from 229 pre-cleanup)
- Only stable, production-ready code
- No test artifacts, temp files, or sensitive configs
- Clean branch structure

Author: CalorieApp Maintainer

.gitignore

@@ -257,6 +257,17 @@ SOCIAL_MEDIA_ANNOUNCEMENT_KIT.md
 test_*.py
 test_*.txt
 *_output.txt
+demo_*.py
+temp_*.py
+
+# Root-level internal files
+/RELEASE_STRATEGY_SUMMARY.md
+/GIT_COMMIT_GUIDE.md
+/COMMIT_QUICK_REFERENCE.md
+/COMPREHENSIVE_TODO_LIST.md
+
+# Config with sensitive test data
+config/test_accounts.json
 
 # Test artifacts
 .pytest_cache/