delete the mappings ledger — per-job in-memory resolution + notes fingerprint guard

The persisted (chatId, sourceId)→node table was a shared namespace across
independent chunk/batch jobs: each chunk's extractor mints local ids fresh
(p1..pN), so later chunks collided with earlier ones — propositions silently
skipped as 'already resolved' (coverage checkpointed anyway: permanent silent
loss) and edges resolved onto the wrong nodes (the 'everything links to
everything' mush). Owner ruling 2026-09-29: mergeFindings resolves THIS job's
ids in memory, nothing persists between jobs; cross-job identity is the
auditor's linkTo verdicts alone.

- contracts: NodeMapping dies; NotesSource.contentFp — sha256 of the text at
  the last run, the re-import guard (unchanged re-import = TRUE no-op, no
  model calls, no usage; changed text re-runs; legacy unstamped sources
  re-run once)
- merger: job-local resolution map, in-submit duplicate ids skip once,
  edges resolve extractor-local ids only
- ports/store: appendMapping/readMappings, LEDGER_FILES.mappings,
  rewriteLedgers.mappings gone (stale data/graph/mappings.jsonl just stops
  being read)
- session-clusters: birthSessionOf is provenance-only — the legacy
  mapping-line fallback for provenance-empty notes nodes dies
- deletion: no mapping rows to strip; stats lose mappingsRemoved
- replay-layout batches nodes by first provenance point
- graph.test pins the new independence semantics (re-merge re-creates;
  duplicate ids within one submit resolve once); extraction tests pin
  per-chunk merges + the fingerprint guard

scripts/replay-layout.ts

@@ -19,7 +19,7 @@ const depthMode: "off" | "vertical" | "radial" =
 	depthArg === "--depth=vertical" ? "vertical" : depthArg === "--depth=radial" ? "radial" : "off";
 import { incrementalLayout } from "../src/core/layout.ts";
 import { birthSessionPartition } from "../src/core/session-clusters.ts";
-import type { GraphNode, NodeMapping, Position } from "../src/core/contracts.ts";
+import type { GraphNode, Position } from "../src/core/contracts.ts";
 
 function main() {
 	const t0 = Date.now();
@@ -35,17 +35,17 @@ function main() {
 	const edges = graphStore.readEdges();
 	// The cluster source (wave 7): the birth-session partition, derived on
 	// read — same as the real settle (core/layout-settle.ts).
-	const birthClusters = birthSessionPartition(nodes, graphStore.readMappings());
+	const birthClusters = birthSessionPartition(nodes);
 
 	// Batches: each imported file, in real import order (sources.json
-	// importedAt). A node belongs to the file whose mapping first claims it
-	// (mapping line order = arrival); nodes no mapping covers (legacy) ride
+	// importedAt). A node belongs to the session of its FIRST provenance
+	// point (line order = arrival); nodes with no provenance (legacy) ride
 	// the final batch.
 	const sources = [...graphStore.readSources()].sort((a, b) => a.importedAt.localeCompare(b.importedAt));
-	const mappings: NodeMapping[] = graphStore.readMappings();
 	const batchOf = new Map<string, string>(); // nodeId → srcId
-	for (const m of mappings) {
-		if (!batchOf.has(m.graphNodeId)) batchOf.set(m.graphNodeId, m.chatId);
+	for (const node of nodes) {
+		const birth = node.provenance[0]?.chatId;
+		if (birth !== undefined && !batchOf.has(node.id)) batchOf.set(node.id, birth);
 	}
 
 	const delivered = new Set<string>();