Effect creation support improved

What is the benefit? Why is this valuable?

Modern UIs have postprocessing shader effects, we need these too

What are common use cases?

Add post-processing effect to Qt DS project

Technical information

User must be able to use existing postprocessing effects and create new ones (using QQEM plugin) easily.

QQEM is part of the Qt 6.5 but this plugin incorporates the functionality of the QQEM to Qt Design Studio.

Minimum set is to have good postprocessing effects that include (list is from Qt Graphical Effects)

• dropshadow
• gaussian blur
• glow
• colorize
• blend