Add server monitoring functionality and update Makefile and requirements

- Introduced a new server monitoring module in `run_helper.py` with graceful shutdown handling.
- Updated `.gitignore` to include PID files.
- Added `test-monitor` target in `Makefile` for testing the server monitoring module.
- Included `psutil` in `requirements.txt` for system monitoring capabilities.

.gitignore

@@ -42,3 +42,8 @@ test.db
 ehthumbs.db
 Thumbs.db
 PERFORMANCE_IMPROVEMENTS.md
+
+# PID files
+*.pid
+helper_bot.pid
+voice_bot.pid