This commit introduces a new header file `nanovg_gl46.h` that implements
the NanoVG rendering context using OpenGL 4.6. The new backend utilizes
Direct State Access (DSA) functions, immutable texture storage, and
explicit layout qualifiers. It includes definitions for creating and
deleting the rendering context, as well as functions for handling images
with OpenGL 4.6.
- Introduced GStreamerTexture class for handling video frames.
- Updated texture loading methods to include FromGStreamer.
- Modified effect handling to support GStreamer textures.
- Updated launch configuration and added new sample scripts.