feat(bearing): plan of a pair with block outline and overlaid drawing values (승인 2026-10-26)

- C4·C5 measured across the coping width (교각축 직각): the two coping edges
  at ±B/2 to the bearing centre. The former along-the-axis definition is replaced.
- view/bearing-plan-svg.ts: the plan of one pair with the model's solplates
  and the block outline(s) (일체: one 2500 × 1200; 분리: two 1200 × 1200), and
  the drawing A/B overlaid as dashed outlines.
- ② bearing card: 상세 보기 pair chips (①·⑥ …) and the overlay toggle.

Co-Authored-By: Claude Haiku 5.5 <noreply@anthropic.com>

tests/bearing-layout.test.ts

@@ -12,14 +12,14 @@ function block(no: number, row: '전열' | '후열', s: number): BlockModel {
 }
 
 describe('받침 배치 규칙 (승인 2026-10-26)', () => {
-  it('C4 and C5 from the model: distances from each coping edge to the bearing centre (P1 ≈ 943 / 950 mm)', () => {
+  it('C4 and C5 from the model: distances from the two coping edges across the width (교각축 직각), P1 front 852 / 2248', () => {
     const d = bearingEdgeDistances(model);
     expect(d).toHaveLength(10);
     const first = d.find((x) => x.no === 1 && x.row === '전열')!;
-    expect(first.leftMm).toBeCloseTo(943, 0);
-    expect(first.rightMm).toBeCloseTo(12000 - 943, 0);
-    // the two ends of one bearing sum to the coping length
-    for (const x of d) expect(x.leftMm + x.rightMm).toBeCloseTo(12000, 6);
+    expect(first.leftMm).toBeCloseTo(852, 0);
+    expect(first.rightMm).toBeCloseTo(2248, 0);
+    // the two edges are one coping width (3100) apart
+    for (const x of d) expect(x.leftMm + x.rightMm).toBeCloseTo(3100, 6);
   });
 
   it('the front and back bearings of one number are about 85 mm apart on P1, so 일체 is allowed', () => {