fix: relax sum > 0 to sum >= 0 for Windows timer resolution

time.monotonic() on Windows can have low enough resolution that
fast in-memory calls measure as 0.0s.

Generated by Mistral Vibe.
Co-Authored-By: Mistral Vibe <vibe@mistral.ai>

Author: verdie-g

tests/shared/test_otel.py

@@ -63,7 +63,7 @@ def greet(name: str) -> str:
     assert tools_call_point["attributes"]["gen_ai.operation.name"] == "execute_tool"
     assert tools_call_point["attributes"]["mcp.protocol.version"] == "2025-11-25"
     assert tools_call_point["count"] == 1
-    assert tools_call_point["sum"] > 0
+    assert tools_call_point["sum"] >= 0
 
     # tools/list is also called during initialization
     assert any(p["attributes"]["mcp.method.name"] == "tools/list" for p in op_points)
@@ -74,7 +74,7 @@ def greet(name: str) -> str:
     assert session_point["attributes"]["mcp.protocol.version"] == "2025-11-25"
     assert "error.type" not in session_point["attributes"]
     assert session_point["count"] == 1
-    assert session_point["sum"] > 0
+    assert session_point["sum"] >= 0
 
 
 @pytest.mark.filterwarnings("ignore::RuntimeWarning")