The MCP server previously created a new PersistentClient on every tool
call via _get_collection(). This incurs HNSW index loading overhead
on each request.
Cache the client and collection at module level. The cache resets
naturally on process restart (MCP runs as a subprocess).
Also adds a _reset_mcp_cache fixture to conftest.py for test isolation.
Includes test infrastructure from PR #131.
92 tests pass.
- Switch CI install step from `pip install -r requirements.txt` to
`pip install -e ".[dev]"` since requirements.txt was removed
- Add noqa: E402 to intentionally-late imports in conftest.py
(HOME must be isolated before mempalace imports)
- Remove unused KnowledgeGraph import in test_knowledge_graph.py
- Apply ruff formatting to test files
Igor Lins e Silva