gh-159118: Use MTA COM initialization in _wmi to avoid crashes under load

Initialize COM with COINIT_MULTITHREADED instead of COINIT_APARTMENTTHREADED in _wmimodule.cpp to prevent hidden window registration contention and RPC_NT_INTERNAL_ERROR crashes under high concurrency.

Author: utam-1

Misc/NEWS.d/next/Windows/2026-10-15-18-45-00.gh-issue-159118.wmiMTA.rst

@@ -0,0 +1 @@
+Fix a crash (``RPC_NT_INTERNAL_ERROR``) and intermittent window class failures in :mod:`!_wmi` under high concurrency and load by initializing COM as multi-threaded (MTA) instead of apartment-threaded (STA).

PC/_wmimodule.cpp

@@ -67,7 +67,7 @@ _query_thread(LPVOID param)
     }
 
     if (SUCCEEDED(hr)) {
-        hr = CoInitializeEx(nullptr, COINIT_APARTMENTTHREADED);
+        hr = CoInitializeEx(nullptr, COINIT_MULTITHREADED);
     }
 
     if (FAILED(hr)) {