feat(#85): IMP catalog builder invariant + VP runtime gate (u1~u7)

- u1: BuilderMissingError(FitError) — narrow exception aligned with pipeline catch
- u2: load_frame_contracts catalog invariant + VP skip + CatalogInvariantError
- u3a: audit CLI I1~I3 (partial existence / declared builder / registry membership)
- u3b: audit CLI I4 (slot_payload refs vs declared/generated payload keys)
- u4: lookup_v4_candidates VP filter (lookup_v4_all_judgments raw telemetry untouched)
- u5: catalog invariant regression coverage + temp non-VP failure fixtures
- u6: mdx04 VP routing fixture tests (sw_dependency_four_problems excluded from live)
- u7: tests/conftest.py env isolation + mdx03/mdx04/mdx05 subprocess smoke

Targeted 74 PASS (12.31s). Full regression 1063 PASS (87.70s). Audit CLI clean.

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

tests/test_audit_frame_invariants_i4.py

@@ -0,0 +1,444 @@
+"""IMP-#85 u3b — Audit CLI invariant I4 (slot_payload ↔ builder generated keys).
+
+Scope (Stage 2 lock):
+  I4 slot_payload refs — every key generated by the contract's builder must
+                          appear as a `slot_payload.<key>` reference in the
+                          partial. Direction A only (dead generated key).
+                          Skipped when the partial uses dynamic bracket
+                          access (`slot_payload[...]`).
+
+  `visual_pending: true` skipped (data-driven from catalog, matches u2/u3a
+  invariant scope; no hard-coded frame allow-list).
+
+Out of scope (별 axis):
+  - V4 runtime VP filter (u4).
+  - Catalog regression coverage suite (u5).
+  - Implementing the 17 missing VP builders.
+"""
+from __future__ import annotations
+
+import subprocess
+import sys
+from pathlib import Path
+
+import yaml
+
+REPO_ROOT = Path(__file__).resolve().parent.parent
+SCRIPT_PATH = REPO_ROOT / "scripts" / "audit_frame_invariants.py"
+
+
+def _write_yaml(path: Path, payload: dict) -> Path:
+    path.write_text(yaml.safe_dump(payload, sort_keys=False), encoding="utf-8")
+    return path
+
+
+def _run_cli(catalog: Path, partials: Path) -> subprocess.CompletedProcess:
+    return subprocess.run(
+        [
+            sys.executable,
+            str(SCRIPT_PATH),
+            "--catalog",
+            str(catalog),
+            "--partials-dir",
+            str(partials),
+        ],
+        cwd=str(REPO_ROOT),
+        capture_output=True,
+        text=True,
+    )
+
+
+def test_prod_catalog_audit_passes_i4():
+    """Prod catalog + prod partials dir → no I4 violations on live contracts."""
+    from scripts.audit_frame_invariants import (
+        DEFAULT_CATALOG_PATH,
+        DEFAULT_PARTIALS_DIR,
+        check_i4_slot_payload_refs,
+    )
+    from src.phase_z2_mapper import PAYLOAD_BUILDERS
+
+    catalog = yaml.safe_load(
+        DEFAULT_CATALOG_PATH.read_text(encoding="utf-8")
+    ) or {}
+    registered = set(PAYLOAD_BUILDERS.keys())
+    violations = check_i4_slot_payload_refs(
+        catalog, DEFAULT_PARTIALS_DIR, registered
+    )
+    assert violations == [], (
+        "Prod live contracts must satisfy I4 (every generated key is "
+        "referenced by the partial, or partial uses dynamic access). "
+        f"Got: {violations}"
+    )
+
+
+def test_extract_static_slot_refs_finds_dot_access():
+    from scripts.audit_frame_invariants import extract_static_slot_refs
+
+    partial = (
+        "{{ slot_payload.title }}\n"
+        "{% if slot_payload.foo %}<b>{{ slot_payload.foo }}</b>{% endif %}\n"
+        "{% for x in slot_payload.bar %}{{ x }}{% endfor %}\n"
+    )
+    refs = extract_static_slot_refs(partial)
+    assert refs == {"title", "foo", "bar"}
+
+
+def test_extract_static_slot_refs_ignores_dynamic_bracket():
+    from scripts.audit_frame_invariants import extract_static_slot_refs
+
+    partial = "{{ slot_payload['pill_' ~ n ~ '_label'] }}"
+    # Dynamic access does NOT contribute dot-access refs.
+    assert extract_static_slot_refs(partial) == set()
+
+
+def test_partial_uses_dynamic_slot_access_detects_bracket():
+    from scripts.audit_frame_invariants import partial_uses_dynamic_slot_access
+
+    dynamic = "{{ slot_payload['pill_' ~ n ~ '_label'] }}"
+    static = "{{ slot_payload.title }} and {{ slot_payload.body }}"
+    assert partial_uses_dynamic_slot_access(dynamic) is True
+    assert partial_uses_dynamic_slot_access(static) is False
+
+
+def test_expected_keys_quadrant_flat_slots_default_pattern():
+    from scripts.audit_frame_invariants import expected_payload_keys
+
+    contract = {
+        "payload": {
+            "title": {"source": "section.title"},
+            "builder": "quadrant_flat_slots",
+            "builder_options": {
+                "item_parser": "quadrant_item",
+                "pad_to": 4,
+                "label_key_pattern": "quadrant_{n}_label",
+                "body_key_pattern": "quadrant_{n}_body",
+            },
+        }
+    }
+    keys = expected_payload_keys(contract)
+    assert "title" in keys
+    for n in range(1, 5):
+        assert f"quadrant_{n}_label" in keys
+        assert f"quadrant_{n}_body" in keys
+
+
+def test_expected_keys_quadrant_flat_slots_custom_pattern():
+    from scripts.audit_frame_invariants import expected_payload_keys
+
+    contract = {
+        "payload": {
+            "title": {"source": "section.title"},
+            "builder": "quadrant_flat_slots",
+            "builder_options": {
+                "item_parser": "quadrant_item",
+                "pad_to": 3,
+                "label_key_pattern": "category_{n}_label",
+                "body_key_pattern": "category_{n}_body",
+            },
+        }
+    }
+    keys = expected_payload_keys(contract)
+    assert keys == {
+        "title",
+        "category_1_label", "category_2_label", "category_3_label",
+        "category_1_body", "category_2_body", "category_3_body",
+    }
+
+
+def test_expected_keys_cycle_intersect_3():
+    from scripts.audit_frame_invariants import expected_payload_keys
+
+    contract = {
+        "payload": {
+            "title": {"source": "section.title"},
+            "builder": "cycle_intersect_3",
+            "builder_options": {
+                "item_parser": "quadrant_item",
+                "pad_to": 3,
+                "label_key_pattern": "circle_{n}_label",
+            },
+        }
+    }
+    keys = expected_payload_keys(contract)
+    assert keys == {
+        "title", "circle_1_label", "circle_2_label", "circle_3_label",
+        "intersection",
+    }
+
+
+def test_expected_keys_compare_table_2col():
+    from scripts.audit_frame_invariants import expected_payload_keys
+
+    contract = {
+        "payload": {
+            "title": {"source": "section.title"},
+            "builder": "compare_table_2col",
+            "builder_options": {"item_parser": "compare_row_2col_item"},
+        }
+    }
+    keys = expected_payload_keys(contract)
+    assert keys == {"title", "col_a_label", "col_b_label", "rows"}
+
+
+def test_expected_keys_paired_rows_4x2_slots():
+    from scripts.audit_frame_invariants import expected_payload_keys
+
+    contract = {
+        "payload": {
+            "title": {"source": "section.title"},
+            "builder": "paired_rows_4x2_slots",
+            "builder_options": {
+                "item_parser": "quadrant_item",
+                "label_key_pattern": "row_{r}_{side}_label",
+                "body_key_pattern": "row_{r}_{side}_body",
+                "rows": 4,
+                "sides": ["left", "right"],
+            },
+        }
+    }
+    keys = expected_payload_keys(contract)
+    assert "title" in keys
+    for r in range(1, 5):
+        for side in ("left", "right"):
+            assert f"row_{r}_{side}_label" in keys
+            assert f"row_{r}_{side}_body" in keys
+
+
+def test_expected_keys_process_product_pair():
+    from scripts.audit_frame_invariants import expected_payload_keys
+
+    contract = {
+        "payload": {
+            "title": {"source": "section.title"},
+            "builder": "process_product_pair",
+            "builder_options": {
+                "pad_sections_to": 3,
+                "columns": [
+                    {"title_to": "banner_left", "body_to": "process",
+                     "body_parser": "column_with_transform"},
+                    {"title_to": "banner_right", "body_to": "product",
+                     "body_parser": "column_with_transform"},
+                ],
+            },
+        }
+    }
+    keys = expected_payload_keys(contract)
+    assert keys == {"title", "banner_left", "process", "banner_right", "product"}
+
+
+def test_expected_keys_items_with_role():
+    from scripts.audit_frame_invariants import expected_payload_keys
+
+    contract = {
+        "payload": {
+            "title": {"source": "section.title"},
+            "builder": "items_with_role",
+            "builder_options": {
+                "item_parser": "pillar_item",
+                "array_root": "pillars",
+            },
+        }
+    }
+    keys = expected_payload_keys(contract)
+    assert keys == {"title", "pillars"}
+
+
+def test_i4_dead_generated_key_flagged(tmp_path):
+    """Builder produces key X, partial doesn't reference it → I4 violation."""
+    from scripts.audit_frame_invariants import check_i4_slot_payload_refs
+
+    partials_dir = tmp_path / "families"
+    partials_dir.mkdir()
+    # Partial only references `title` — missing category_2_label / _body etc.
+    (partials_dir / "drift_frame.html").write_text(
+        "<div>{{ slot_payload.title }}</div>"
+        "<div>{{ slot_payload.category_1_label }}</div>"
+        "<div>{{ slot_payload.category_1_body }}</div>",
+        encoding="utf-8",
+    )
+    catalog = {
+        "drift_frame": {
+            "template_id": "drift_frame",
+            "payload": {
+                "title": {"source": "section.title"},
+                "builder": "quadrant_flat_slots",
+                "builder_options": {
+                    "item_parser": "quadrant_item",
+                    "pad_to": 2,
+                    "label_key_pattern": "category_{n}_label",
+                    "body_key_pattern": "category_{n}_body",
+                },
+            },
+        },
+    }
+    violations = check_i4_slot_payload_refs(
+        catalog, partials_dir, registered_builders={"quadrant_flat_slots"}
+    )
+    msgs = "\n".join(violations)
+    assert "I4 generated-key-orphan" in msgs
+    assert "drift_frame" in msgs
+    assert "category_2_label" in msgs
+    assert "category_2_body" in msgs
+    # category_1 keys ARE referenced — must NOT be flagged.
+    assert "slot_payload.category_1_label." not in msgs
+    assert "slot_payload.category_1_body." not in msgs
+
+
+def test_i4_skips_partial_with_dynamic_bracket_access(tmp_path):
+    """Dynamic bracket access in partial → I4 skipped (cannot resolve statically)."""
+    from scripts.audit_frame_invariants import check_i4_slot_payload_refs
+
+    partials_dir = tmp_path / "families"
+    partials_dir.mkdir()
+    (partials_dir / "dynamic_frame.html").write_text(
+        "{{ slot_payload.title }}\n"
+        "{% for n in range(1, 6) %}"
+        "{{ slot_payload['pill_' ~ n ~ '_label'] }}"
+        "{{ slot_payload['pill_' ~ n ~ '_body'] }}"
+        "{% endfor %}",
+        encoding="utf-8",
+    )
+    catalog = {
+        "dynamic_frame": {
+            "template_id": "dynamic_frame",
+            "payload": {
+                "title": {"source": "section.title"},
+                "builder": "quadrant_flat_slots",
+                "builder_options": {
+                    "item_parser": "quadrant_item",
+                    "pad_to": 5,
+                    "label_key_pattern": "pill_{n}_label",
+                    "body_key_pattern": "pill_{n}_body",
+                },
+            },
+        },
+    }
+    violations = check_i4_slot_payload_refs(
+        catalog, partials_dir, registered_builders={"quadrant_flat_slots"}
+    )
+    assert violations == [], (
+        "Dynamic bracket access must suppress I4 (cannot resolve statically); "
+        f"got: {violations}"
+    )
+
+
+def test_i4_skips_visual_pending(tmp_path):
+    """VP contract with drift → I4 skip (no violation)."""
+    from scripts.audit_frame_invariants import check_i4_slot_payload_refs
+
+    partials_dir = tmp_path / "families"
+    partials_dir.mkdir()
+    (partials_dir / "vp_frame.html").write_text(
+        "<div>nothing</div>", encoding="utf-8"
+    )
+    catalog = {
+        "vp_frame": {
+            "template_id": "vp_frame",
+            "visual_pending": True,
+            "payload": {
+                "title": {"source": "section.title"},
+                "builder": "quadrant_flat_slots",
+                "builder_options": {
+                    "item_parser": "quadrant_item", "pad_to": 4,
+                },
+            },
+        },
+    }
+    violations = check_i4_slot_payload_refs(
+        catalog, partials_dir, registered_builders={"quadrant_flat_slots"}
+    )
+    assert violations == []
+
+
+def test_i4_skips_unregistered_builder(tmp_path):
+    """Unregistered builder (already an I3 hit) → I4 silent on same contract."""
+    from scripts.audit_frame_invariants import check_i4_slot_payload_refs
+
+    partials_dir = tmp_path / "families"
+    partials_dir.mkdir()
+    (partials_dir / "ghost_frame.html").write_text(
+        "{{ slot_payload.title }}", encoding="utf-8"
+    )
+    catalog = {
+        "ghost_frame": {
+            "template_id": "ghost_frame",
+            "payload": {
+                "title": {"source": "section.title"},
+                "builder": "ghost_builder_not_in_registry",
+            },
+        },
+    }
+    violations = check_i4_slot_payload_refs(
+        catalog, partials_dir, registered_builders={"quadrant_flat_slots"}
+    )
+    assert violations == [], (
+        "Unregistered builder is already flagged by I3 — I4 must stay silent "
+        f"on the same contract; got: {violations}"
+    )
+
+
+def test_i4_skips_missing_partial(tmp_path):
+    """Missing partial (already I1 hit) → I4 silent on same contract."""
+    from scripts.audit_frame_invariants import check_i4_slot_payload_refs
+
+    partials_dir = tmp_path / "families"
+    partials_dir.mkdir()
+    # No partial file written.
+    catalog = {
+        "missing_partial_frame": {
+            "template_id": "missing_partial_frame",
+            "payload": {
+                "title": {"source": "section.title"},
+                "builder": "quadrant_flat_slots",
+                "builder_options": {
+                    "item_parser": "quadrant_item", "pad_to": 4,
+                },
+            },
+        },
+    }
+    violations = check_i4_slot_payload_refs(
+        catalog, partials_dir, registered_builders={"quadrant_flat_slots"}
+    )
+    assert violations == []
+
+
+def test_cli_pass_on_prod_paths(tmp_path):
+    """End-to-end CLI on prod paths reports PASS with I1-I4 wording."""
+    result = subprocess.run(
+        [sys.executable, str(SCRIPT_PATH)],
+        cwd=str(REPO_ROOT),
+        capture_output=True,
+        text=True,
+    )
+    assert result.returncode == 0, result.stdout + result.stderr
+    assert "PASS (I1-I4 clean" in result.stdout
+
+
+def test_cli_fail_on_synthetic_i4_drift(tmp_path):
+    """CLI exits 1 + emits I4 violation when a non-VP contract has dead keys."""
+    partials_dir = tmp_path / "families"
+    partials_dir.mkdir()
+    (partials_dir / "drift_frame.html").write_text(
+        "{{ slot_payload.title }}", encoding="utf-8"
+    )
+    catalog_path = _write_yaml(
+        tmp_path / "frame_contracts.yaml",
+        {
+            "drift_frame": {
+                "template_id": "drift_frame",
+                "payload": {
+                    "title": {"source": "section.title"},
+                    "builder": "quadrant_flat_slots",
+                    "builder_options": {
+                        "item_parser": "quadrant_item", "pad_to": 2,
+                        "label_key_pattern": "category_{n}_label",
+                        "body_key_pattern": "category_{n}_body",
+                    },
+                },
+            },
+        },
+    )
+    result = _run_cli(catalog_path, partials_dir)
+    assert result.returncode == 1, result.stdout + result.stderr
+    assert "I4 generated-key-orphan" in result.stdout
+    assert "category_1_label" in result.stdout