IMP-05 deterministic V4 candidate bridge — pre-render rank-2/3 fallback + trace schema + dedup invariant test

round 55~73 review-loop lock per Codex #11 final + Claude #13 6-axis L1~L9.

Scope (deterministic only) :
- pre-render rank-2/3 fallback via lookup_v4_match_with_fallback (selector only,
  no calculate_fit migration, no AI, no full planner rerun, no layout topology change,
  no abort behavior change)
- Step 9 informative candidate_evidence schema (additive) — v4_label / phase_z_status
  / catalog_registered / filtered_for_direct_execution / route_hint / decision / reason
- Step 20 qualifier fields (additive) — fallback_used / fallback_selection_count
  / selection_paths[] — top-level enum unchanged
- restructure / reject candidates preserved as non-direct evidence with route hints
  (design_reference_only / ai_adaptation_required) — deferred actual handlers IMP-29/IMP-31
- catalog 1:1 invariant test (separate file tests/test_catalog_invariant.py) —
  fails fast if template_id/frame_id 1:1 mapping ever breaks
- 6 behavior tests fully synthetic with MOCK_ prefix (no real catalog IDs,
  no v4_full32_result.yaml dependency) — monkeypatch get_contract +
  compute_capacity_fit (selector has no DI, function signature unchanged)

Deferred to follow-up issues :
- IMP-30 first-render invariant + abort bypass (zero-unit + section status filter)
- IMP-29 frontend zone-level override (deterministic only)
- IMP-31 AI-assisted frame-aware adaptation

Guardrails locked : no calculate_fit / no AI / no frontend / no full rerun /
no layout topology / no abort behavior change / no 1-2 sample hardcoding.

Tests : 8/8 pass (6 selector behavior + 2 catalog invariant).
Smoke regression : 11/11 partials pass (IMP-04 F17 calibration intact).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tests/test_catalog_invariant.py

@@ -0,0 +1,81 @@
+"""Phase Z catalog invariant test — real `frame_contracts.yaml` 1:1 mapping verify.
+
+IMP-05 L4 lock per Claude #13 §3 :
+  - real catalog read (purpose 자체 = real catalog 검증)
+  - template_id ↔ frame_id 1:1 mapping (Codex #6 terminology — 2 reference keys for same entry)
+  - fail fast with explicit message if catalog policy changes
+
+Codex #5 verified : 11 templates / 11 frames, all unique = 1:1 mapping confirm (2026-05-13).
+Codex #7 generalization guardrail : real catalog OK (purpose 자체) — NOT sample-hardcoding.
+"""
+from __future__ import annotations
+
+from pathlib import Path
+
+import pytest
+import yaml
+
+PROJECT_ROOT = Path(__file__).parent.parent
+CATALOG_PATH = PROJECT_ROOT / "templates" / "phase_z2" / "catalog" / "frame_contracts.yaml"
+
+
+def _load_catalog() -> dict:
+    with CATALOG_PATH.open(encoding="utf-8") as f:
+        return yaml.safe_load(f)
+
+
+def test_catalog_template_id_to_frame_id_one_to_one():
+    """Verify each catalog entry has unique template_id + unique frame_id (1:1 reference keys).
+
+    Fails fast if the catalog policy ever drifts from this assumption — IMP-05 dedup
+    relies on `template_id` as the runtime key and assumes one frame per template.
+    """
+    catalog = _load_catalog()
+
+    template_ids = []
+    frame_ids = []
+    for entry_key, entry in catalog.items():
+        if not isinstance(entry, dict):
+            continue
+        tid = entry.get("template_id")
+        fid = entry.get("frame_id")
+        assert tid is not None, f"entry {entry_key} missing template_id"
+        assert fid is not None, f"entry {entry_key} missing frame_id"
+        template_ids.append(tid)
+        frame_ids.append(str(fid))
+
+    duplicate_templates = [t for t in template_ids if template_ids.count(t) > 1]
+    duplicate_frames = [f for f in frame_ids if frame_ids.count(f) > 1]
+
+    assert not duplicate_templates, (
+        "Phase Z catalog currently expects one template_id per frame_id; "
+        "update dedup policy if this changes. "
+        f"Duplicate template_ids found: {set(duplicate_templates)}"
+    )
+    assert not duplicate_frames, (
+        "Phase Z catalog currently expects one template_id per frame_id; "
+        "update dedup policy if this changes. "
+        f"Duplicate frame_ids found: {set(duplicate_frames)}"
+    )
+    assert len(template_ids) == len(frame_ids), (
+        "Phase Z catalog template_id count must equal frame_id count "
+        f"(templates={len(template_ids)}, frames={len(frame_ids)})."
+    )
+
+
+def test_catalog_entry_count_matches_frame_count():
+    """Sanity guard — each entry contributes one template_id + one frame_id."""
+    catalog = _load_catalog()
+    entry_count = sum(1 for v in catalog.values() if isinstance(v, dict))
+    template_count = sum(
+        1 for v in catalog.values()
+        if isinstance(v, dict) and v.get("template_id") is not None
+    )
+    frame_count = sum(
+        1 for v in catalog.values()
+        if isinstance(v, dict) and v.get("frame_id") is not None
+    )
+    assert entry_count == template_count == frame_count, (
+        f"catalog shape inconsistent: entries={entry_count} "
+        f"templates={template_count} frames={frame_count}"
+    )