Initialize the Windows COM library on all threads

Use threading model `COINIT_APARTMENTTHREADED` on threads that own a window (the main client thread) and `COINIT_MULTITHREADED` on all other threads.

Add assertions to ensure that the COM library is initialized successfully and only once per thread.

References:

- https://learn.microsoft.com/en-us/windows/win32/learnwin32/initializing-the-com-library
- https://learn.microsoft.com/en-us/windows/win32/com/single-threaded-apartments
- https://learn.microsoft.com/en-us/windows/win32/com/multithreaded-apartments

Yet another attempt at solving #5744.

src/base/system.cpp

@@ -719,6 +719,9 @@ static unsigned long __stdcall thread_run(void *user)
 #error not implemented
 #endif
 {
+#if defined(CONF_FAMILY_WINDOWS)
+	CWindowsComLifecycle WindowsComLifecycle(false);
+#endif
 	struct THREAD_RUN *data = (THREAD_RUN *)user;
 	void (*threadfunc)(void *) = data->threadfunc;
 	void *u = data->u;
@@ -4252,9 +4255,12 @@ int net_socket_read_wait(NETSOCKET sock, std::chrono::nanoseconds nanoseconds)
 }
 
 #if defined(CONF_FAMILY_WINDOWS)
-CWindowsComLifecycle::CWindowsComLifecycle()
+// See https://learn.microsoft.com/en-us/windows/win32/learnwin32/initializing-the-com-library
+CWindowsComLifecycle::CWindowsComLifecycle(bool HasWindow)
 {
-	CoInitializeEx(NULL, COINIT_APARTMENTTHREADED | COINIT_DISABLE_OLE1DDE);
+	HRESULT result = CoInitializeEx(NULL, (HasWindow ? COINIT_APARTMENTTHREADED : COINIT_MULTITHREADED) | COINIT_DISABLE_OLE1DDE);
+	dbg_assert(result != S_FALSE, "COM library already initialized on this thread");
+	dbg_assert(result == S_OK, "COM library initialization failed");
 }
 CWindowsComLifecycle::~CWindowsComLifecycle()
 {

src/base/system.h

@@ -2563,11 +2563,14 @@ public:
 /**
  * This is a RAII wrapper to initialize/uninitialize the Windows COM library,
  * which may be necessary for using the open_file and open_link functions.
+ * Must be used on every thread. It's automatically used on threads created
+ * with thread_init. Pass true to the constructor on threads that own a
+ * window (i.e. pump a message queue).
  */
 class CWindowsComLifecycle
 {
 public:
-	CWindowsComLifecycle();
+	CWindowsComLifecycle(bool HasWindow);
 	~CWindowsComLifecycle();
 };
 #endif

src/engine/client/client.cpp

@@ -4574,7 +4574,7 @@ int main(int argc, const char **argv)
 #if defined(CONF_PLATFORM_ANDROID)
 	const char **argv = const_cast<const char **>(argv2);
 #elif defined(CONF_FAMILY_WINDOWS)
-	CWindowsComLifecycle WindowsComLifecycle;
+	CWindowsComLifecycle WindowsComLifecycle(true);
 #endif
 	CCmdlineFix CmdlineFix(&argc, &argv);
 	bool Silent = false;

src/engine/server/main.cpp

@@ -62,6 +62,10 @@ int main(int argc, const char **argv)
 		}
 	}
 
+#if defined(CONF_FAMILY_WINDOWS)
+	CWindowsComLifecycle WindowsComLifecycle(false);
+#endif
+
 	std::vector<std::shared_ptr<ILogger>> vpLoggers;
 #if defined(CONF_PLATFORM_ANDROID)
 	vpLoggers.push_back(std::shared_ptr<ILogger>(log_logger_android()));