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.

Makefile

@@ -1,4 +1,4 @@
-.PHONY: help test test-db test-coverage test-html clean install
+.PHONY: help test test-db test-coverage test-html clean install test-monitor
 
 # Default target
 help:
@@ -11,6 +11,7 @@ help:
 	@echo "  test-errors  - Run error handling tests only"
 	@echo "  test-utils   - Run utility functions tests only"
 	@echo "  test-keyboards - Run keyboard and filter tests only"
+	@echo "  test-monitor - Test server monitoring module"
 	@echo "  test-coverage - Run tests with coverage report (helper_bot + database)"
 	@echo "  test-html    - Run tests and generate HTML coverage report"
 	@echo "  clean        - Clean up generated files"
@@ -49,6 +50,10 @@ test-utils:
 test-keyboards:
 	python3 -m pytest tests/test_keyboards_and_filters.py -v
 
+# Test server monitoring module
+test-monitor:
+	python3 tests/test_monitor.py
+
 # Run tests with coverage
 test-coverage:
 	python3 -m pytest tests/ --cov=helper_bot --cov=database --cov-report=term
@@ -69,5 +74,7 @@ clean:
 	rm -f .coverage
 	rm -f database/test.db
 	rm -f test.db
+	rm -f helper_bot.pid
+	rm -f voice_bot.pid
 	find . -type d -name "__pycache__" -exec rm -rf {} +
 	find . -type f -name "*.pyc" -delete