Wave 7 chunk B: remove the embeddings machinery — the ladder collapses

The owner's wave-7 ruling: embeddings die entirely (git history is the
stash); clustering is birth-session derived (chunk A, 950ddfd), labels
are session names, and the prober's graph tools replace injection.

- settings: GraphSettings collapses to { enabled } — embedding,
  embeddingModel, clustering, labeling all die. Migration story: stale
  record keys are UNREAD and dropped by the sanitizer's reconstruction;
  the next graph-section PUT (replace-whole) persists the collapsed
  shape. The settings-panel GraphSection renders one master row.
- deleted: src/server/embeddings.ts (adapters, resolveEmbeddingPortFor,
  embedNewNodes, embeddingPort, embeddingModelCatalog), the
  GET /api/models/embeddings route, scripts/embed-graph.ts, tests for
  all three, and the /api/models/embeddings picker surfaces in the UI.
- prices: EMBEDDING_PRICES overlay + callCost fallback die. cost-summary:
  the embedding stage fold dies — back to three stages (extraction/
  audit/naming) per the owner ruling; historical stages.embedding spend
  in old run records is simply not displayed.
- ports: EmbeddingPort/EmbeddingResult/EmbeddingTask die. The embeddings
  LEDGER surface (readEmbeddings/writeEmbeddings + EmbeddingsLedger +
  EMBEDDINGS_FILE + graph-deletion's vector pruning) STAYS — inert data,
  kept only so graph-context.ts compiles until Teacher's pass removes
  it; the seam dies in the follow-up interlude.
- chat-handler (approved cross-lane unwiring, wave-6 precedent): the
  extraction pipeline's embedder becomes a documented no-op (nothing
  embedded, nothing spent, ledger untouched) until Teacher's pass
  removes the phase; the graph-context injection dispatch gate, the
  graphContext deps wiring, the setContextRespawn seam, and
  turn-service's triggerGraphContext are gone — injection is dead
  code pending Teacher's file deletions.
- scripts: backfill-graph/import-notes pass the same no-op embedder;
  replay-layout derives clusters from birthSessionPartition (the same
  partition the real settle uses) instead of the embeddings ledger.
- settings-body: parseGraphSettingsBody reads the master switch only —
  old-shape keys in a body are ignored, not rejected; bad shapes 400.
- next.config: the @huggingface tracing-exclusion guards die with the
  last reference.

Cross-lane flags: extraction.ts/graph-context.ts keep stale embed
comments + the embed phase until Teacher's full pass (their parallel
interlude owns those files — zero overlap kept by design);
semantic-clusters.ts + its test stay one more round (extraction.test.ts,
Teacher's file, still imports it — they delete it with the namer cases);
ChatSettings.graphContextTokens + the graph-context-control UI stay
until Teacher+UI.

Gates: tsc clean, eslint clean, 885/885 tests, build compiles.
Live-verified on the port-3004 dev tree: PUT /api/settings/graph with
dead keys collapses on write, bad shapes 400, GET reads {enabled: true},
/api/models/embeddings 404s.

src/server/settings-body.ts

@@ -289,41 +289,22 @@ export function parseAppearanceSettingsBody(body: unknown): SettingsBodyResult<A
 	return { ok: true, settings };
 }
 
-/** graph: the four-rung ladder { enabled?, embedding?, clustering?, labeling? }
- *  + embeddingModel? — the BYOK provider embedding model (wave 6,
- *  2026-09-23): null or a "provider:id" slug of a shipped provider.
- *  Catalog validity is network-dependent — the parser checks SHAPE only
- *  (the federated /api/models/embeddings gives the picker real options). */
+/** graph: the collapsed section { enabled? } (wave 7, owner ruling
+ *  2026-09-23): the master switch ONLY — the embedding/clustering/labeling
+ *  rungs and the BYOK embeddingModel died with the provider embedder
+ *  (clustering is the free birth-session partition, labels are session
+ *  names). Old-shape keys in a body are ignored, not rejected. */
 export function parseGraphSettingsBody(body: unknown): SettingsBodyResult<GraphSettings> {
 	const raw = asRecord(body);
 	if (!raw) return { ok: false, error: "Invalid JSON body" };
+	// Wave 7 collapse (owner ruling 2026-09-23): the section is the master
+	// switch ONLY. PUT is replace-whole — a body like {enabled: true} IS the
+	// whole section now; the dead rungs' keys in old records are unread
+	// (the sanitizer drops them; see sanitizeGraph).
 	const settings: GraphSettings = {};
-	for (const key of ["enabled", "embedding", "clustering", "labeling"] as const) {
-		if (raw[key] !== undefined) {
-			if (typeof raw[key] !== "boolean") {
-				return { ok: false, error: `${key} must be a boolean` };
-			}
-			settings[key] = raw[key];
-		}
-	}
-	if (raw.embeddingModel !== undefined) {
-		if (raw.embeddingModel !== null) {
-			// NOTE: the id may itself contain colons (OpenRouter suffixes like
-			// "liquid/lfm-2.5-embedding-350m:free") — the provider is the part
-			// before the FIRST colon, so the id half just forbids whitespace.
-			if (
-				typeof raw.embeddingModel !== "string" ||
-				!/^(openrouter|openai|google):\S+$/.test(raw.embeddingModel)
-			) {
-				return {
-					ok: false,
-					error: 'embeddingModel must be null or a "openrouter|openai|google:model-id" slug',
-				};
-			}
-			settings.embeddingModel = raw.embeddingModel;
-		} else {
-			settings.embeddingModel = null;
-		}
+	if (raw.enabled !== undefined) {
+		if (typeof raw.enabled !== "boolean") return { ok: false, error: "enabled must be a boolean" };
+		settings.enabled = raw.enabled;
 	}
 	return { ok: true, settings };
 }