fix(layer): refresh ribbon and layer panel when entities register novel layers

src/scene/entity.rs

@@ -143,13 +143,17 @@ impl Scene {
     /// layer 0. Auto-registering keeps it on its own layer (#252). Names are
     /// registered verbatim so the writer's (case-insensitive) lookup matches;
     /// the always-present default layer "0" and empty names are no-ops.
-    pub fn ensure_layer(&mut self, name: &str) {
-        if name.trim().is_empty() || self.document.layers.contains(name) {
-            return;
+    pub fn ensure_layer(&mut self, name: &str) -> bool {
+        let trimmed = name.trim();
+        if trimmed.is_empty() || trimmed == "0" || self.document.layers.contains(trimmed) {
+            return false;
         }
-        let mut layer = codec::tables::Layer::new(name);
+        let mut layer = codec::tables::Layer::new(trimmed);
         layer.handle = self.document.allocate_handle();
         let _ = self.document.layers.add(layer);
+        self.invalidate_layer_dependencies(&[trimmed.to_string()]);
+        self.layer_table_dirty = true;
+        true
     }
 
     pub(crate) fn ensure_app_id(&mut self, name: &str) {

src/scene/mod.rs

@@ -2054,6 +2054,9 @@ pub struct Scene {
     pub preview_text: Vec<crate::scene::pipeline::text_gpu::TextVertex>,
     /// Committed-segment wire drawn during multi-point commands (normal colour).
     pub interim_wire: Option<WireModel>,
+    /// Set when an entity creation or update automatically registers a novel
+    /// layer into the document layer table, signalling the UI to refresh.
+    pub layer_table_dirty: bool,
     pub camera_generation: u64,
     /// Incremented whenever geometry-affecting state changes (entities, selection,
     /// preview wires, layer visibility, layout). The GPU pipeline uses this to
@@ -2626,6 +2629,7 @@ impl Scene {
             preview_hatches: Arc::new(Vec::new()),
             preview_text: vec![],
             interim_wire: None,
+            layer_table_dirty: false,
             camera_generation: 0,
             geometry_epoch: GEOMETRY_EPOCH.fetch_add(1, Ordering::Relaxed),
             projection_bounds_epoch: std::cell::Cell::new(0),