Hash-based compaction has issues

[abrookins]

Hash-based compaction is behaving oddly:

00:08:10 agent_memory_server.long_term_memory INFO   Starting hash-based duplicate compaction
00:08:10 agent_memory_server.long_term_memory INFO   Found 54 groups of hash-based duplicates
00:08:10 agent_memory_server.long_term_memory INFO   Completed hash-based deduplication. Merged 0 memories.
00:08:10 agent_memory_server.long_term_memory INFO   Starting semantic duplicate compaction
00:08:10 agent_memory_server.long_term_memory INFO   Using index 'memory_records' for semantic duplicate compaction.
00:08:10 agent_memory_server.long_term_memory INFO   Found 53 memories to check for semantic duplicates
00:08:25 agent_memory_server.long_term_memory INFO   Completed semantic deduplication. Merged 0 memories.
00:08:25 agent_memory_server.long_term_memory INFO   Memory compaction completed in 15.25s. Merged 0 memories. 53 memories remain.

[abrookins]

Fixed by #41