Fix import errors, shadowing, and openapi serialization issues

app/monitoring/memory_sniper.py

@@ -0,0 +1,18 @@
+import tracemalloc
+import logging
+from fastapi import Request
+
+# Start tracing at import time (once per process)
+tracemalloc.start()
+
+def log_memory_snapshot(request: Request | None = None):
+    """Take a memory snapshot and log top 5 memory consumers.
+    Optionally include request info for context.
+    """
+    snapshot = tracemalloc.take_snapshot()
+    top_stats = snapshot.statistics('lineno')
+    logging.info('[MEMORY SNAPSHOT] Top 5 Memory Consumers:')
+    for idx, stat in enumerate(top_stats[:5], start=1):
+        logging.info(f"#{idx}: {stat.traceback.format()[-1].filename}:{stat.traceback.format()[-1].lineno} - {stat.size / 1024:.2f} KiB")
+    if request:
+        logging.info(f'Request path: {request.url.path}')