fix: address Copilot review — derive MCP version, improve test isolation and portability

tests/conftest.py

@@ -37,7 +37,8 @@ from mempalace.knowledge_graph import KnowledgeGraph  # noqa: E402
 @pytest.fixture(autouse=True)
 def _reset_mcp_cache():
     """Reset the MCP server's cached ChromaDB client/collection between tests."""
-    yield
+
+    def _clear_cache():
         try:
             from mempalace import mcp_server
 
@@ -46,6 +47,10 @@ def _reset_mcp_cache():
         except (ImportError, AttributeError):
             pass
 
+    _clear_cache()
+    yield
+    _clear_cache()
+
 
 @pytest.fixture(scope="session", autouse=True)
 def _isolate_home():

tests/test_mcp_server.py

@@ -151,9 +151,10 @@ class TestReadTools:
         assert result["taxonomy"]["project"]["frontend"] == 1
         assert result["taxonomy"]["notes"]["planning"] == 1
 
-    def test_no_palace_returns_error(self, monkeypatch, config, kg):
+    def test_no_palace_returns_error(self, monkeypatch, config, kg, tmp_path):
-        config._file_config["palace_path"] = "/nonexistent/path"
+        missing = str(tmp_path / "missing")
-        _patch_mcp_server(monkeypatch, config, "/nonexistent/path", kg)
+        config._file_config["palace_path"] = missing
+        _patch_mcp_server(monkeypatch, config, missing, kg)
         from mempalace.mcp_server import tool_status
 
         result = tool_status()

tests/test_searcher.py

@@ -30,8 +30,8 @@ class TestSearchMemories:
         result = search_memories("code", palace_path, n_results=2)
         assert len(result["results"]) <= 2
 
-    def test_no_palace_returns_error(self):
+    def test_no_palace_returns_error(self, tmp_path):
-        result = search_memories("anything", "/nonexistent/path")
+        result = search_memories("anything", str(tmp_path / "missing"))
         assert "error" in result
 
     def test_result_fields(self, palace_path, seeded_collection):