feat(view): add visual style previews

- preview render modes on hover without committing
- distinguish 2D and 3D wireframe fill and depth behavior

Refs #483

src/modules/draw/modify/trim.rs

@@ -4570,6 +4570,7 @@ fn preview_wire(points: Vec<[f32; 3]>, color: [f32; 4], name: &str) -> WireModel
         world_width: 0.0,
         depth_override: None,
         fill_is_3d: false,
+        fill_is_2d_solid: false,
         pick_tris: Vec::new(),
         pick_tris_low: Vec::new(),
         dash_from_start: false,