SL-20611 Make haze effect local lights.  Incidental fix for EventPump coroutine sometimes doing unsafe work mid-render.

SL-20611 Followup -- fix edge cases with transparent PBR objects around eye/object above/below water.

Likely happened because some textures had 0 height width initially, but
this is for UI/preview so request maximum either way.

scale thumbnail textures down to 256 when needed. As we do to chat icons.

# Conflicts:
#	indra/newview/llviewertexture.cpp

SL-20553: Fix crash in ~PBRPickerAgentListener

SL-20611 Make haze effect local lights -- move sky and water haze to their own passes and unify sky and water haze in forward rendering shaders.

* SL-20570 Fix for lossy (and square) normal maps when importing GLTF materials.

* SL-20582 Fix for overriding to alpha mode blend not working.  Incidental decruft of dead code (thanks, Rye!)

SL-20553: Save material button in build floater now depends on agent inventory rather than object inventory

SL-20553: Save material button in build floater now depends on agent inventory rather than object inventory