fix(view): correct 3D mesh interaction

Sync projection controls from the active camera, preserve the UCS icon in perspective views, and use visible or selected 3D geometry for orbit pivots. Dense mesh vertex grips remain hidden.

src/entities/mesh.rs

@@ -1101,11 +1101,7 @@ impl RenderConvertible for Mesh {
 
 impl Grippable for Mesh {
     fn grips(&self) -> Vec<GripDef> {
-        self.vertices
-            .iter()
-            .enumerate()
-            .map(|(i, v)| square_grip(i, glam::DVec3::new(v.x, v.y, v.z)))
-            .collect()
+        Vec::new()
     }
 
     fn apply_grip(&mut self, grip_id: usize, apply: GripApply) {