feat(v3-data-store): harden search security and standardize test suite

tests/README.md

@@ -44,6 +44,16 @@ These consolidated scripts are the primary verification tool for the V3 API.
 2.  **Archiving**: When a new specialized test is created, check if it can be combined into one of the "Primary" suites above. If so, combine and move the original to `archive/`.
 3.  **Cleanup**: Always use `tests/e2e/cleanup_test_files.py` after running file lifecycle tests.
 
+## 🛠️ Standards & Patterns
+
+To maintain a "nice" and readable test suite, follow these patterns in all new Python E2E scripts:
+
+- **Helper Functions**: Use a `print_result(label, success, message="")` helper to output standardized `✅ PASS` and `❌ FAIL` status lines.
+- **Functional Isolation**: Wrap test scenarios in descriptive functions (e.g., `test_hierarchical_fallback()`) rather than writing monolithic scripts.
+- **Vision Compliance**: Always verify that IDs in the response are strings (Random IDs) and not integers, to ensure "ID Vision" is working.
+- **Performance Logging**: Include a suite timer at the end of the `if __name__ == "__main__":` block to track execution speed.
+- **Clean Environment**: Do not leave temporary debug or local-only scripts in the `e2e/` directory.
+
 ---
 
 ## 🚀 How to Run