View-dependent display refinement: finer curved faces and edges as you zoom in (#1320) (#1425)

* View-dependent display refinement: bodies seen up close are drawn from finer display plans (#1320)

Each frame the viewport works out every shown body's screen-space error (the display
quality's chord tolerance in pixels where the body is nearest the eye) and picks a
refinement step past the chosen display quality, each halving the chord, with hysteresis.
Steps are planned off the UI thread and swapped in when ready, within a triangle budget
and a cache size. Faces (GPU plan or CPU mesh), edges, silhouettes and highlights of a
refined body all come from the refined plan, so a highlight stays on the drawn triangles.
Planned bodies are chunked by content on the GPU, so a refinement re-evaluates only its
own chunk. Display only: the reference mesh, the B-rep and exports never change.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Display refinement: only collect finished plans while the view stands still, time the choice, keep the web planning one step a frame

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Format

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Keep the Display quality note as it was (the longer one pushed the Colour vision list off the Graphics page)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

crates/ui-egui/src/control.rs

@@ -245,6 +245,7 @@ fn dispatch(app: &mut SolveApp, ctx: &egui::Context, method: &str, p: &Value) ->
             "file_picker_busy": app.file_picker_busy(),
             "file_dialog_open": app.file_picker_busy(),
             "build_ms": app.viewport.build_ms,
+            "display_lod": app.viewport.lod.lock().map(|l| serde_json::to_value(&l.stats).unwrap_or_default()).unwrap_or_default(),
             "preview": {"active": app.preview.active, "busy": app.preview.busy, "error": app.preview.error, "ms": app.preview.ms, "replaced": app.preview.replaced},
             "home": app.home.open,
             "recent_thumbnails_ready": app.home.ready_recents(),