refactor(display): trim isolines follow-up comments

src/app/mod.rs

@@ -517,9 +517,7 @@ pub(super) struct OpenCADStudio {
     crosshair_color: Option<[u8; 3]>,
     /// Editable Options buffer for the crosshair colour.
     crosshair_color_input: String,
-    /// Set while the isolines slider is being dragged with a value that
-    /// differs from the drawing's, so the costly mesh rebuild runs once on
-    /// release rather than on every pixel of the drag.
+    /// Defer the ISOLINES mesh rebuild until the slider is released.
     isolines_awaiting_regen: bool,
     /// Edit buffer for the SNAPANG field on the Options Drafting page. Kept
     /// separate from `snap_angle_deg` so a half-typed angle is not parsed.