Solari light trails fix?

## What problem does this solve or what need does it fill?

Noticeable GI update "lag / trail / delay ect..." for moving lights.

## What solution would you like?

Not expert. IMO: Split light cash into fast and slow? "Fast" will use less frames for accumulation, but higher spatial resolution. Slow will use less "rays" and accumulate longer?
This will apply to lights and meshes. Something like slow/static mesh+ static light ?
User can "mark" meshes and light into groups of priority?
This solution uses more memory and potentially slower but gives user more control .

## What alternative(s) have you considered?

Ignore.

The issue describes GI update lag and trails for moving lights in Solari. No files, tests, or entry points are identified, and the proposed solution is exploratory; first determine where light and mesh accumulation is implemented and how the current behavior is tested. Done would require an agreed design and verified improvement for moving lights.

Written by the indexing model from the issue text.