feat(tht): sync-schema-linking projects F4 ledger into schema_linking.json

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

harness/tht/session/store.py

@@ -181,6 +181,51 @@ def set_schema_linking(
     return path
 
 
+def sync_schema_linking(session_id: str, sessions_root: Path) -> Path:
+    """Project the effective F4 ledger decisions into schema_linking.json.
+
+    candidates/excluded are rebuilt from table_promoted/table_excluded +
+    column_promoted/column_excluded (last decision per subject wins). question,
+    joins, concept_formulas and open_questions are preserved from the existing
+    file when present. The reviewer's curation is thus authoritative and
+    deterministic (no model transcription)."""
+    from tht.phase import effective_decisions
+
+    session_dir = sessions_root / session_id
+    manifest = load_session(session_id, sessions_root)
+
+    existing: dict = {}
+    sl_path = session_dir / "schema_linking.json"
+    if sl_path.exists():
+        existing = json.loads(sl_path.read_text())
+
+    # last decision per subject wins (handles a re-run of the gate).
+    latest: dict[str, str] = {}
+    for d in effective_decisions(session_dir):
+        if d.type in ("table_promoted", "table_excluded", "column_promoted", "column_excluded"):
+            latest[d.subject] = d.type
+
+    candidates: list[dict] = []
+    excluded: list[dict] = []
+    for subject, dtype in latest.items():
+        is_column = "." in subject
+        kind = "column" if is_column else "table"
+        if dtype in ("table_promoted", "column_promoted"):
+            candidates.append({"kind": kind, "name": subject, "decision": "promoted"})
+        else:
+            excluded.append({"kind": kind, "name": subject})
+
+    data = {
+        "question": existing.get("question") or manifest.question,
+        "candidates": candidates,
+        "joins": existing.get("joins", []),
+        "excluded": excluded,
+        "open_questions": existing.get("open_questions", []),
+        "concept_formulas": existing.get("concept_formulas", []),
+    }
+    return set_schema_linking(session_id, data, sessions_root)
+
+
 def load_session(session_id: str, sessions_root: Path) -> SessionManifest:
     path = sessions_root / session_id / MANIFEST
     if not path.exists():