feat: enhance database transactions, add Makefiles, and improve Docker setup

- Refactored database batch operations to ensure transaction atomicity and simplify nested structure.
- Added `Makefile` for `knowledge-base` and `llm-gateway` modules to streamline development workflows.
- Simplified `Dockerfile` for `llm-gateway` by removing multi-stage builds and optimizing dependencies.
- Improved code readability in `collection_manager` and `failover` modules with refined logic.
- Minor fixes in `test_server` and Redis health check handling for better diagnostics.

mcp-servers/knowledge-base/tests/test_server.py

@@ -1,8 +1,7 @@
 """Tests for server module and MCP tools."""
 
-import json
 from datetime import UTC, datetime
-from unittest.mock import AsyncMock, MagicMock, patch
+from unittest.mock import AsyncMock, MagicMock
 
 import pytest
 from fastapi.testclient import TestClient