refactor: drop residual zero-subtraction from world_offset removal

In the files where ox/oy/oz came solely from the now-zero offset
destructure (tessellate, block_cache, dimension, leader, text_support),
remove the `let [ox,oy,oz] = [0,0,0]` binding and the `- ox` arithmetic so
the coordinate math reads as the plain absolute value it now is.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/entities/leader.rs

@@ -589,9 +589,8 @@ impl LeaderTess for Leader {
             entity_color
         };
         let name = handle.value().to_string();
-        let [ox, oy, oz] = [0.0_f64; 3];
         let p3 = |v: &acadrust::types::Vector3| -> [f32; 3] {
-            [(v.x - ox) as f32, (v.y - oy) as f32, (v.z - oz) as f32]
+            [(v.x) as f32, (v.y) as f32, (v.z) as f32]
         };
         let nan = [f32::NAN; 3];