feat(catalog): activate bim_current_problems_paired (IMP-04 Track A 8/16)

V4 signal = restructure 1 (4 MDX sample). Catalog-completeness activation —
Codex round 51 guardrail (per-frame source-evidence check, not blind F16
reuse). Source confirmed as 2x2 paired-rows BIM problem layout, distinct
from F16's quadrant-4 framing.

3-layer architecture (matrix §0) :
- V4 = matching authority — restructure tier signal; runtime activation
  prepares Phase Z to assemble this frame when V4 ranks it.
- figma_to_html (1171281194) = source/evidence — 4 BIM problem cards in
  2x2 grid (개념 부재 / 잘못된 접근방식 / 방향성 상실 / 전제조건 오류).
- Phase Z = runtime — adds catalog + partial + smoke fixture.

Builder reuse :
- `quadrant_flat_slots` reused with pad_to=4 + `issue_{n}_label/body` keys.
- `quadrant_item` parser reused.
- F16 quadrant pattern reused, but the partial is a 2-row × 2-column
  problem-theme grid (red/orange/amber/deep-amber), not the F16 TL/TR/BL/BR
  quadrant visual. Source-evidence-driven decision per Codex round 51 §10.

3 file changes :

1. templates/phase_z2/families/bim_current_problems_paired.html
   - 2x2 CSS grid with per-issue problem theme.
   - PROMOTED CSS : per-cell warning gradient (red/orange/amber/deep-amber),
     title gradient (zone-title family), "!" bullet markers in per-cell color.
   - NOT PROMOTED : Figma source banner / numbered badges / texture —
     figma_to_html source evidence preserved for future fidelity review.
   - ADAPTED : Figma absolute positioning → CSS grid 2x2, token-fixed
     typography.

2. templates/phase_z2/catalog/frame_contracts.yaml — F17 contract appended
   - frame_id=1171281194, family=cards, source_shape=top_bullets, strict 4,
     role_order=[issue_1..issue_4].
   - visual_hints.min_height_px = 350 (F16/F14 class — 2-row × 2-col density).
   - accepted_content_types = [text_block].
   - payload.builder = quadrant_flat_slots reuse with issue_{n}_* keys.

3. scripts/smoke_frame_render.py — bundled fixture for F17.

Verification :
- python scripts/smoke_frame_render.py --self-check : PASS 11/11 (F17 at
  3856 chars CSS-only)
- python scripts/smoke_frame_render.py bim_current_problems_paired
  --render-to data/runs/imp04_f17_visual : PASS, 0 raster refs
- python run_mdx03_pipeline.py --phase-z2 --run-id imp04_f17_regression :
  PASS (MDX 03 V4 rank-1 unchanged; F17 not in MDX 03 V4 selection so
  this is non-impacting regression check)

scope-lock honored : V4 logic / mapper / production render / Phase R' /
AI/Kei / 10 existing partials all unchanged.

4-class status :
- class 1 readiness : ✅
- class 2 content-fit : watch — paragraph-heavy source (each issue body
  is multi-line Korean text). Compact 2x2 cell may need wrap. max-content
  fit checked via R3 artifact.
- class 3 : N/A
- class 4 : N/A

Refs Gitea #4 (IMP-04 Track A frame 8 — V4 RS tier, source-evidence-confirmed)

scripts/smoke_frame_render.py

@@ -280,6 +280,17 @@ SELF_CHECK_FIXTURES: dict[str, dict] = {
         "emphasis_3_label": "실무 적용 불가",
         "emphasis_3_body": [{"text": "특수성 반영 어려움", "indent": 0}],
     },
+    "bim_current_problems_paired": {
+        "title": "현황 및 문제점",
+        "issue_1_label": "개념 부재",
+        "issue_1_body": [{"text": "CAD 확장판 오인", "indent": 0}],
+        "issue_2_label": "잘못된 접근방식",
+        "issue_2_body": [{"text": "도구로만 인식", "indent": 0}],
+        "issue_3_label": "방향성 상실",
+        "issue_3_body": [{"text": "대형 S/W 의존", "indent": 0}],
+        "issue_4_label": "전제조건 오류",
+        "issue_4_body": [{"text": "건축·토목 혼용", "indent": 0}],
+    },
 }