Clusters phases B+C: labeling records, the naming call, snapshot payload

Core-survival labelings (vision section 1, DECIDED 2026-09-13):
ClusterLabeling records in a new append-only ledger
(data/graph/cluster-labels.jsonl), immutable, id = clu_ + sha256 of the
sorted core so re-naming races and re-runs dedupe at the store seam.
matchClusterLabelings (core/clusters.ts, pure): a community keeps a
record's label while at least half its core survives in it; both sides
single-successor (a split keeps one name; greedy by overlap, ties to
the newer record).

The namer (src/agent/subagents/cluster-namer.ts): ONE singular cheap LLM
call (new 'labeler' role, glm-flash/low) names every new/changed
community at once, given member names + statements (capped at 12
members per cluster). refreshClusterLabels runs POST-EXTRACTION
(user-decided) from both front doors, fire-and-forget — naming failure
never fails the run; refreshes serialize behind a chain so parallel
imports never mint duplicate labels. import-notes.ts awaits
clusterNamingSettled before exit.

Payload: GraphSnapshot.clusters (>= MIN_CLUSTER_SIZE 3) joins detection
with labelings at read time — claimed clusters carry the record's label
and id; unlabeled ones carry a member-hash id and null label. Detection
is deterministic so no memo in v1 (ms at current scale; revisit at
vault scale).

Tests (372/372): matcher half-rule/split/merge/greedy/tie cases; naming
end-to-end through importNotes (one call, one record, claim on
re-refresh), naming failure non-fatal; snapshot derivation with
labeling join; 11 test pipelines now pin an explicit labeler seam.

scripts/import-notes.ts

@@ -15,6 +15,7 @@
 import * as fs from "node:fs";
 import * as path from "node:path";
 import { createExtractionPipeline } from "../src/agent/subagents/extraction.ts";
+import { clusterNamingSettled } from "../src/agent/subagents/cluster-namer.ts";
 import { getGraph } from "../src/core/graph.ts";
 import { stores } from "../src/server/stores.ts";
 
@@ -52,10 +53,16 @@ async function main() {
 	});
 	await Promise.all(workers);
 
+	// The post-merge cluster naming is fire-and-forget inside the pipeline;
+	// settle it before the process exits so labels actually land.
+	await clusterNamingSettled();
+
 	const graph = getGraph(stores.graphStore);
+	const labels = stores.graphStore.readClusterLabels().length;
 	console.log(
 		`[import-notes] done: +${totals.nodes} nodes, +${totals.edges} edges, +${totals.events} events, ${totals.failed} failed — ` +
-			`graph now ${graph.nodes.length} nodes, ${graph.edges.length} edges, ${graph.events.length} events`,
+			`graph now ${graph.nodes.length} nodes, ${graph.edges.length} edges, ${graph.events.length} events, ` +
+			`${labels} named clusters`,
 	);
 }