Viewer: the locked viewer shares the main viewer's display key (#619 follow-up)

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01QiAJeFttZp83Fh7YuzAR5f

crates/ui-egui/src/panels/viewer.rs

@@ -523,9 +523,7 @@ fn locked_pane(app: &mut EffectcraftApp, ui: &mut egui::Ui, full: Rect, bg: Colo
         .then(|| app.session.state.views3d.get(&lv.comp).cloned().unwrap_or_default().cam(lv.view, comp.width as f64, comp.height as f64).state());
     let dc = effectcraft_engine::viewer::DisplayColor::of(&app.session);
     // The display conversion's inputs, keyed as in the main viewer's texture caches.
-    let sim = app.session.state.viewer.simulation;
-    let custom = if sim.profile == effectcraft_engine::viewer::SimProfile::MyCustom { format!("{:?}", app.session.prefs.custom_rgb) } else { String::new() };
-    let dc_key = format!("{cam:?}{}{sim:?}{}{custom}", dc.is_some(), app.session.prefs.previews.display_profile);
+    let dc_key = format!("{cam:?}{}", super::viewer_tools::display_key(app, dc.is_some()));
     let key = {
         use std::hash::{Hash, Hasher};
         let mut h = std::collections::hash_map::DefaultHasher::new();