chore: remove dead UI helpers and orphan toolbar stubs

Each item below was gated by #[allow(dead_code)] and has zero callers
across src/ — none of them are part of any public API consumed by
external crates (this is a binary, not a library):

* modules/insert/underlay_frames.rs + edit_aliases.rs — toolbar stubs
  whose `tool()` registrars were never wired into the ribbon; the
  parent mod.rs inlines its own include_bytes! for the SVGs, so the
  files were orphan dead weight.
* ui/snap_popup.rs:snap_marker_color — never called.
* ui/ribbon/mod.rs:last_dropdown_cmd — never called.
* ui/scale_popup.rs:anno_scale_for_label — never called.
* ui/layers.rs:color_name_to_aci — inverse of aci_color_display
  with zero call sites.
* linetypes.rs:name_list — never called.
* scene/pipeline/wire_gpu.rs:new_ghost — never called.

Co-Authored-By: Claude Opus 4.7 <[email protected]>

src/ui/layers.rs

@@ -838,22 +838,6 @@ fn color_label_aci(i: u8) -> &'static str {
     }
 }
 
-#[allow(dead_code)]
-fn color_name_to_aci(name: &str) -> u8 {
-    match name {
-        "red" => 1,
-        "yellow" => 2,
-        "green" => 3,
-        "cyan" => 4,
-        "blue" => 5,
-        "magenta" => 6,
-        "white" => 7,
-        "dark gray" => 8,
-        "gray" => 9,
-        _ => 7,
-    }
-}
-
 pub fn iced_color_from_acad(c: &AcadColor) -> Color {
     match c {
         AcadColor::Index(i) => {

src/ui/ribbon/mod.rs

@@ -180,15 +180,6 @@ impl Ribbon {
         self.open_dropdown = None;
     }
 
-    #[allow(dead_code)]
-    pub fn last_dropdown_cmd(
-        &self,
-        dropdown_id: &'static str,
-        default: &'static str,
-    ) -> &'static str {
-        self.last_cmd.get(dropdown_id).copied().unwrap_or(default)
-    }
-
     // ── View ──────────────────────────────────────────────────────────────
 
     pub fn view(

src/ui/scale_popup.rs

@@ -23,15 +23,6 @@ const COMMON_SCALES: &[(&str, f32, f64)] = &[
     ("10:1", 0.1, 10.00),
 ];
 
-#[allow(dead_code)]
-pub fn anno_scale_for_label(label: &str) -> f32 {
-    COMMON_SCALES
-        .iter()
-        .find(|&&(l, _, _)| l == label)
-        .map(|&(_, a, _)| a)
-        .unwrap_or(1.0)
-}
-
 /// Full-screen overlay: transparent click-catcher + scale list panel pinned bottom-right.
 ///
 /// - `is_model`: true = model space (dispatches SetAnnotationScale), false = paper space (SetViewportScale).

src/ui/snap_popup.rs

@@ -233,27 +233,3 @@ const LABEL_OFF: Color = Color {
     a: 1.0,
 };
 
-/// The `Point` parameter is unused today; kept for future tooltip positioning.
-#[allow(dead_code)]
-pub fn snap_marker_color(snap_type: SnapType) -> Color {
-    match snap_type {
-        SnapType::Endpoint | SnapType::Midpoint => Color {
-            r: 1.0,
-            g: 0.9,
-            b: 0.1,
-            a: 1.0,
-        },
-        SnapType::Grid => Color {
-            r: 0.4,
-            g: 0.9,
-            b: 0.4,
-            a: 1.0,
-        },
-        _ => Color {
-            r: 1.0,
-            g: 0.9,
-            b: 0.1,
-            a: 1.0,
-        },
-    }
-}