feat: publish authoritative fabric cutover export

Assistant: codex
Assistant-Model: gpt-5.6-sol
Assistant-Session: 01a053ff-1d6f-7fe2-ac1c-a6eb40a42a0c

railiance_fabric/registry.py

@@ -16,6 +16,7 @@ from .financial import (
     materialize_financial_graph_export,
     merge_financial_graph_exports,
 )
+from .financial_baseline import financial_export_from_legacy
 from .loader import load_yaml, repo_root
 from .schema_validation import draft202012_validator
 
@@ -470,10 +471,11 @@ class RegistryStore:
     def combined_graph(self) -> dict[str, Any]:
         snapshots = self.latest_snapshots()
         if snapshots and all(is_financial_graph_export(snapshot["graph"]) for snapshot in snapshots):
-            return merge_financial_graph_exports(
+            graph = merge_financial_graph_exports(
                 [snapshot["graph"] for snapshot in snapshots],
                 generated_at=_utc_now(),
             )
+            return _with_registry_provenance(graph, snapshots)
         nodes: dict[str, dict[str, Any]] = {}
         edges: list[dict[str, str]] = []
         for snapshot in snapshots:
@@ -491,14 +493,21 @@ class RegistryStore:
                 nodes[node_id] = node
         for edge in projected_edges:
             edges.append(_edge_with_canon_metadata(edge))
-        return {
+        graph = {
             "apiVersion": "railiance.fabric/v1alpha1",
             "kind": "FabricGraphExport",
             "generated_at": _utc_now(),
-            "source": {"repo": "registry", "commit": "", "path": ""},
             "nodes": [nodes[key] for key in sorted(nodes)],
             "edges": sorted(edges, key=lambda edge: (edge["from"], edge["to"], edge["type"])),
         }
+        return _with_registry_provenance(graph, snapshots)
+
+    def financial_graph(self) -> dict[str, Any]:
+        """Return the accepted graph through the financial Fabric contract."""
+        graph = self.combined_graph()
+        if is_financial_graph_export(graph):
+            return graph
+        return financial_export_from_legacy(graph)
 
     def add_artifact(self, payload: dict[str, Any]) -> dict[str, Any]:
         repo_slug = _required_text(payload, "repo_slug")
@@ -1394,6 +1403,35 @@ def _with_source(graph: dict[str, Any], repo_slug: str, commit: str, generated_a
     return copy
 
 
+def _with_registry_provenance(
+    graph: dict[str, Any], snapshots: list[dict[str, Any]]
+) -> dict[str, Any]:
+    """Identify the exact accepted snapshot set behind a combined export."""
+    copy = json.loads(json.dumps(graph))
+    revisions = [
+        {
+            "repo_slug": str(snapshot["repo_slug"]),
+            "commit": str(snapshot["commit"]),
+            "generated_at": str(snapshot["generated_at"]),
+        }
+        for snapshot in sorted(
+            snapshots,
+            key=lambda item: (str(item["repo_slug"]), str(item["commit"])),
+        )
+    ]
+    raw = json.dumps(revisions, sort_keys=True, separators=(",", ":"), ensure_ascii=True)
+    revision_digest = hashlib.sha256(raw.encode("utf-8")).hexdigest()
+    copy["source"] = {
+        "producer": "railiance-fabric",
+        "repo": "railiance-fabric",
+        "registry": "accepted-snapshots",
+        "commit": f"snapshot-set:sha256:{revision_digest}",
+        "path": "registry://accepted-snapshots",
+        "snapshots": revisions,
+    }
+    return copy
+
+
 def _snapshot_dict(row: sqlite3.Row) -> dict[str, Any]:
     return {
         "id": row["id"],