feat: VirtualScrollView simplification

[marc2332]

Depends #268

• No need to Box the builder
• Simple caching of elements

[codecov]

Codecov Report

Attention: 20 lines in your changes are missing coverage. Please review.

Comparison is base (590a0e0) 54.27% compared to head (204a2e4) 54.29%.
Report is 3 commits behind head on main.

Files	Patch %	Lines
...components/src/scroll_views/virtual_scroll_view.rs	0.00%	16 Missing ⚠️
crates/devtools/src/tabs/tree.rs	0.00%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #478      +/-   ##
==========================================
+ Coverage   54.27%   54.29%   +0.02%     
==========================================
  Files         154      155       +1     
  Lines       13540    13590      +50     
==========================================
+ Hits         7349     7379      +30     
- Misses       6191     6211      +20     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.