perf: remove large drawing stalls

Keep resident geometry and GPU resources stable across edits, MSPACE zoom, and Model/Paper switches. Add unified PERF output for tracing remaining costs.

src/lib.rs

@@ -11,6 +11,7 @@ pub mod modules;
 pub mod patreon;
 pub mod videos;
 pub mod plugin;
+pub mod perf;
 pub mod scene;
 pub mod snap;
 pub mod ui;