fix: 거더 높이 변경 시 씬 미갱신 + 받침 치수 오류 수정

[버그 1] Apply 후 카메라 자동 피트 누락
- rebuild_mesh() 에서 scene_extents 만 업데이트하고 camera target/radius 는
  갱신하지 않아, 거더 높이를 올려도 카메라가 구 씬 중심을 가리켜 변화가 안 보임.
- 수정: rebuild_mesh() 끝에 camera.zoom_extents(mn, mx) + update_camera() 추가.

[버그 2] bearing.rs plan_length / plan_width 방향 오류
- plan_length(350mm, 경간 방향)를 profile X(횡방향)에, plan_width(450mm, 횡방향)를
  sweep Z(경간방향)에 사용 → 받침이 90° 회전된 치수로 생성됨.
- Z 센터링 오프셋도 plan_width/2=225mm 로 계산 → 올바른 plan_length/2=175mm 보다
  50mm 더 교대 밖으로 튀어나옴 (스크린샷의 부유 블록).
- 수정:
  · bearing.rs: trans_dim=plan_width(profile X), span_dim=plan_length(sweep Z)
  · bridge_scene.rs: build_bridge_scene + build_selectable_scene 의 Z 오프셋을
    z - 225 → z - plan_length/2 = z - 175 로 변경.

cargo check --workspace 0 errors/warnings.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

cimery/crates/viewer/src/bridge_scene.rs

@@ -171,6 +171,9 @@ pub fn build_bridge_scene<K: GeomKernel>(kernel: &K, p: &SceneParams) -> Result<
 
     // ── Bearings ───────────────────────────────────────────────────────────────
     // 5 per abutment, one under each girder
+    // plan_length(350mm) = 경간 방향 → half = 175mm 으로 Z 센터링.
+    const BEARING_PLAN_LEN: f32 = 350.0;
+    const BEARING_PLAN_WID: f32 = 450.0;
     for &z in &[0.0_f32, span_mm] {
         for i in 0..n_girders {
             let x = (i as f32 - (n_girders as f32 - 1.0) * 0.5) * spacing;
@@ -178,14 +181,15 @@ pub fn build_bridge_scene<K: GeomKernel>(kernel: &K, p: &SceneParams) -> Result<
                 id:                FeatureId::new(),
                 station:           if z < 1.0 { 0.0 } else { span_m },
                 bearing_type:      BearingType::Elastomeric,
-                plan_length:       350.0,
-                plan_width:        450.0,
+                plan_length:       BEARING_PLAN_LEN as f64,
+                plan_width:        BEARING_PLAN_WID as f64,
                 total_height:      BEARING_H as f64,
                 capacity_vertical: 1_500.0,
             };
             let mut mesh = kernel.bearing_mesh(&bearing_ir)?;
             mesh.recolor(COL_BEARING);
-            parts.push(translate(mesh, x, 0.0, z - 225.0));
+            // Z 중심 = 교대 위치(z). bearing mesh Z = [0, plan_length] → 오프셋 = z - plan_length/2.
+            parts.push(translate(mesh, x, 0.0, z - BEARING_PLAN_LEN * 0.5));
         }
     }
 
@@ -383,18 +387,20 @@ pub fn build_selectable_scene<K: GeomKernel>(
     out.push(FeatureMesh { mesh: deck, label: "바닥판 슬래브".into() });
 
     // Bearings
+    // plan_length(350mm) = 경간 방향 → Z 센터링 오프셋 = z - 175.
+    const SEL_BEARING_LEN: f32 = 350.0;
     for &z in &[0.0_f32, span_mm] {
         for i in 0..n_girders {
             let x = (i as f32 - (n_girders as f32 - 1.0) * 0.5) * spacing;
             let bir = BearingIR {
                 id: FeatureId::new(), station: if z < 1.0 { 0.0 } else { span_m },
                 bearing_type: BearingType::Elastomeric,
-                plan_length: 350.0, plan_width: 450.0,
+                plan_length: SEL_BEARING_LEN as f64, plan_width: 450.0,
                 total_height: BEARING_H as f64, capacity_vertical: 1_500.0,
             };
             let mut mesh = kernel.bearing_mesh(&bir)?;
             mesh.recolor(COL_BEARING);
-            for v in &mut mesh.vertices { v[0] += x; v[2] += z - 225.0; }
+            for v in &mut mesh.vertices { v[0] += x; v[2] += z - SEL_BEARING_LEN * 0.5; }
             let side = if z < 1.0 { "시작" } else { "종점" };
             out.push(FeatureMesh { mesh, label: format!("받침 {}-{}", side, i + 1) });
         }

cimery/crates/viewer/src/lib.rs

@@ -492,6 +492,9 @@ impl RenderState {
         let (mn, mx) = scene_extents(&self.params);
         self.scene_mn = mn;
         self.scene_mx = mx;
+        // Apply 후 씬 범위에 맞게 카메라 자동 피트 (거더 높이 변경 등이 즉시 보이도록).
+        self.camera.zoom_extents(mn, mx);
+        self.update_camera();
         self.dirty = false;
     }