Remove unused imports across multiple modules

Cleaned up various files by removing unused or redundant import statements to improve code readability and reduce potential confusion. No functional changes were made.

src/common/cache_manager.py

@@ -1,8 +1,6 @@
 import time
 import json
 import hashlib
-import inspect
-import os
 from pathlib import Path
 import numpy as np
 import faiss