* fix: enforce ownership check on user-memory collection queries
fix: enforce ownership check on user-memory collection queries
Prevent authenticated users from querying other users' memory
collections via the /query/doc and /query/collection endpoints.
A new _validate_collection_access helper rejects requests for
user-memory-{UUID} collections where the UUID does not match
the requesting user. Admins bypass the check.
* Update retrieval.py
* Update retrieval.py