feat(rebar,view): coping end height h1, taper h2 and Level width as inputs on ② (1단계)

The three values are inputs on the coping card, with the P1 values (1000 · 1500 · 2100) when absent, and they are tracked
like the other shape inputs. The geometry and the coping rebar read them from one CopingGeom: the U heights follow the
closed form (h1 − 2c) + h2·min(x_s, x_L0)/x_L0, which reproduces the P1 values. The side rows are assumed to keep their
position relative to the Level underside (명세 확인 필요). P1 results are unchanged; the full suite passes.

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

src/main.ts

@@ -15,6 +15,7 @@ import { shearSegments } from './core/rebar/coping';
 import { buildRebar3D, type RebarColorMode, type RebarScene } from './view/rebar3d';
 import { DEFAULT_MATERIAL, FCK_MEMBERS, fyOf, GRADE_CHOICES, isAssumedMaterial, materialFrom, type BendFactors, type FckByMember, type FckMember, type GradeKey, type Material } from './core/rebar/common';
 import { buildQuantity, quantityRows, type Quantity, type QuantityLine } from './core/rebar/quantity';
+import { P1_COPING_GEOM } from './core/coping-geom';
 import { allVisibleChecked, setVisibleChecked, type TypeFilter } from './core/selection';
 import { choose, defaultSummary, isSelectable, SHAPE_GROUPS, UNDEFINED_REASON, type MemberId } from './core/shape-options';
 import { parseProject, SCHEMA_VERSION, serializeProject, type ProjectFile, type ProjectInfo } from './core/project';
@@ -56,7 +57,7 @@ const CRS = '국토좌표계 (x = 동, y = 북)';
 /** 시안 ② 부재 목록 (spec §5.2). `keys` are the inputs that exist today; the rest show values only. */
 const MEMBERS: { id: MemberId; label: string; keys: EditableKey[]; note: string }[] = [
   { id: 'bearing', label: '교량받침·받침블럭·솔플레이트', keys: [], note: '받침 상세(C3)는 Q16 결정 후 추가합니다. 지금은 표시만 합니다.' },
-  { id: 'coping', label: '코핑', keys: ['copingWidthMm', 'copingLengthMm'], note: '폭과 길이를 입력합니다. 계단 위치·단차선 입력은 다음 단계에서 추가합니다.' },
+  { id: 'coping', label: '코핑', keys: ['copingWidthMm', 'copingLengthMm', 'copingH1Mm', 'copingH2Mm', 'levelWidthMm'], note: '폭, 길이, 끝단 높이 h1, 테이퍼 높이 h2, Level 폭을 입력합니다. 계단 위치·단차선 입력은 다음 단계에서 추가합니다.' },
   { id: 'column', label: '기둥', keys: [], note: '기둥 지름 입력은 다음 단계에서 추가합니다. 높이와 위치는 계산값입니다.' },
   { id: 'footing', label: '확대기초 · 말뚝', keys: ['pileLengthMm'], note: '말뚝 길이를 입력합니다. 열별 본수는 다음 단계에서 추가합니다.' },
   { id: 'ground', label: '지반·지층', keys: [], note: '지반고는 입력값을 표시만 합니다. 지층 입력은 다음 단계에서 추가합니다.' },
@@ -180,7 +181,18 @@ function animate(): void {
 animate();
 
 // --- pier model ----------------------------------------------------------------
-function buildEntry(input: PierInput, checked: boolean): Pier {
+/** Fills the coping heights and Level width with the P1 values when a file or sheet does not give them (1단계). */
+function withCopingDefaults(input: PierInput): PierInput {
+  return {
+    ...input,
+    copingH1Mm: input.copingH1Mm ?? P1_COPING_GEOM.h1,
+    copingH2Mm: input.copingH2Mm ?? P1_COPING_GEOM.h2,
+    levelWidthMm: input.levelWidthMm ?? P1_COPING_GEOM.levelWidth,
+  };
+}
+
+function buildEntry(rawInput: PierInput, checked: boolean): Pier {
+  const input = withCopingDefaults(rawInput);
   const issues: Issue[] = [];
   let model: PierModel | null = null;
   if (validateInput(input, issues)) {
@@ -971,7 +983,7 @@ function renderRebar(): void {
   renderMaterial();
   // 전단철근 구간 표 (시안 ③ 코핑 탭): segments of C9 / C10 / C11 along the coping, in metres.
   if (state.rebarMember === 'coping') {
-    const seg = shearSegments(pier.model.copingL * 1000, pier.model.columns.map((c) => c.s * 1000));
+    const seg = shearSegments(pier.model.copingL * 1000, pier.model.columns.map((c) => c.s * 1000), pier.model.copingGeom);
     const st = el('table', undefined, 'grid-table rebar-table');
     const sh = el('thead');
     const shr = el('tr');