[brush-editing] Summary of release blockers

[andybak]

Summary
0 - fix this on the Quest.... Or maybe do a PC only release initially

1. The sometimes not saving properly issue (this is the big one) --- [rare, suggested beta test]
2. Not being able to modify a modified brush as a new brush (feature probably not a bug) -- [feature gap, can wait]
3. Extended pallette fix for sliders (only relevant to unity brushes at this time) -- [may need extension if too many params exposed]
4. Doesn't appear to accept textures into a folder (optional feature, would be nice to have) -- [you selected as a priority]
5. Your biggest feature request for the Editable Brushes branch was "a quicker way to scroll through the list". That makes total sense now.

As soon as you add the folder (4),
(5) navigation is going to be needed because someone will dump a big textures file in there and start getting brush happy