feat: replace 2 m placeholder with station pattern table from the workbook (Task 5)

Source: RAG 지보패턴현황_20260918.xlsx, sheet 참고_지보패턴현황, 당진방향 table
(4+740..5+500, 42 contiguous rows). Lining pattern (M column) per station now
drives the lining colour and the viewer readout. Daesan table kept as reference
only (WL-4 there, not applied). Drawing patterns E-1, E-2, RP-2, WL-3 are in
neither table and stay [미확정].

Co-Authored-By: Claude Haiku 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01A5Cun3RHQKna9qxE6ybZ4A

scripts/build_skeleton.py

@@ -80,11 +80,13 @@ def ring_world(R, s):
     P = np.column_stack([x - ORIGIN[0] + xs * nx, y - ORIGIN[1] + xs * ny, zr + zs])
     return P
 
-PAL = {"NP-4AD-1-D-2": (231, 111, 81, 255), "NP-4BD-1-D-2": (244, 162, 97, 255),
-       "NP-5AE-1-WL-4": (233, 196, 106, 255), "NP-5BE-1-WL-4": (138, 177, 125, 255),
-       "NP-6A": (42, 157, 143, 255), "NP-6B": (38, 70, 83, 255)}
-ZONES = [(int(r["seg_from"]), int(r["seg_to"]), r["pattern"], r["status"])
-         for r in csv.DictReader(open(f"{ROOT}/data/pattern_zones_placeholder.csv", encoding="utf-8"))]
+PAL = {"A": (42, 157, 143, 255), "B-1": (231, 111, 81, 255), "B-2": (244, 162, 97, 255),
+       "C-1": (233, 196, 106, 255), "C-2": (138, 177, 125, 255), "D-1": (38, 70, 83, 255),
+       "D-2": (100, 130, 160, 255), "P-2": (190, 110, 140, 255), "P-3": (150, 90, 60, 255),
+       "RP-1": (80, 170, 200, 255), "WL-1": (200, 200, 120, 255), "WL-2": (120, 90, 170, 255),
+       "개착부": (170, 170, 170, 255)}
+ZONES = [(int(float(r["sta_from"])), int(float(r["sta_to"])), r["lining_pattern"], "엑셀 지보패턴표(당진방향)")
+         for r in csv.DictReader(open(f"{ROOT}/data/pattern_stations_dangjin.csv", encoding="utf-8"))]
 
 def pattern_of(sta):
     for a, b, pat, _ in ZONES:
@@ -168,7 +170,7 @@ checks["road_z_5480_m"] = round(float(np.interp(S1, dg_s, dg_v)), 3)
 L_chord = float(np.sum([math.dist(cn[i, 1:], cn[i + 1, 1:]) for i in range(len(cn) - 1)]))
 checks["plan_chord_length_total_m (4+700..5+500)"] = round(L_chord, 3)
 checks["station_range_modelled"] = f"{S0} .. {S1} (ring step {DS} m, {len(stations)} rings)"
-checks["pattern_zones (2 m, placeholder)"] = len(ZONES)
+checks["pattern_zones (지보패턴표 당진방향)"] = len(ZONES)
 checks["pattern_coverage_all_stations"] = bool(all(pattern_of(x) in PAL for x in stations))
 checks["pattern_counts"] = {k: sum(1 for z in ZONES if z[2] == k) for k in PAL}
 checks["glb_bytes"] = int(__import__("os").path.getsize(glb))
@@ -188,9 +190,9 @@ meta = {
                      "superelevation sign convention assumed (z += S/100 * x, x = left of tangent)"],
   "layers": [p.metadata["name"] for p in parts],
   "ring_step_m": DS, "ring_points": int(parts[0].metadata["ring_points"]), "first_station": S0,
-  "pattern_status": "PLACEHOLDER: 2 m 임의 배정. 실제 측점 구간 아님 (사용자 결정 2026-10-21). data/pattern_zones_placeholder.csv 를 수정 후 재빌드",
+  "pattern_status": "지보패턴: 엑셀 참고_지보패턴현황 당진방향 표(4+740~5+500, 42행, 빈틈 없음) 적용. 출처 data/pattern_stations_dangjin.csv (사용자 결정 2026-10-21)",
   "patterns": [{"from": a, "to": b, "pattern": pat} for a, b, pat, _ in ZONES],
-  "open": ["4+700~4+745 and 5+480~5+500 excluded ([미확정])", "pattern zones (03-003~008) pending Task 5",
+  "open": ["4+700~4+745 and 5+480~5+500 excluded ([미확정])", "지보패턴 측점표 적용(당진). 도면 E-1~2, RP-2, WL-3~4 는 당진 표에 없어 [미확정]. 대산 표 WL-4(4+758.85~4+768.85)는 참고만 [확인 필요]",
            "lining reference recorded (meta.lining_reference, 04-004~009); sheet-to-station mapping [미확정]",
            "[확정 2026-10-21] R1 6,982 mm 유지 (사용자 결정). 라이닝 도면 6장의 R1 6.892 m 표기는 확인 대상 오기로 기록", "pattern-group to excavation-pattern mapping: user explanation conflicts with filename (WL-4) - re-confirm [확인 필요]"]
 }