Add videocapture_depth.cpp sample #25410
The PR is to combine the examples `videocapture_openni.cpp`, `videocapture_realsense.cpp` and `videocapture_obsensor.cpp` into `videocapture_depth.cpp`.
Tested cameras and OS using this sample are listed below:
| | Windows 10 | Ubuntu 22.04 | Mac M1 14.3 |
|------------------------|--------------|--------------|---------------|
| Orbbec Gemini 2 Series | ✓ | ✓ | ✓ |
| RealSense D435, D455 | ✓ | ✓ | ✗ |
| Kinect, XtionPRO | - | - | - |
Note:
- OpenNI based cameras (Kinect, XtionPRO) are not tested as I don't have them.
- RealSense D435 and D455 don't work on Mac with OpenCV.