Context-meter amendment: CONTEXT_LIMITS dies — pi's live catalog is the only limit source

Owner ruling (2026-09-23, amendment to 04e336d): no hardcoded fallback
exists anywhere. contextWindow(record, limits) resolves the denominator
ONLY from the live index (provider:id -> contextWindow straight from
pi's catalog); a model missing from it (historical session, package
update, failed fetch) reads limit null and the meter renders
usage-only — the honest-render precedent, never a fake window.

- src/core/prices.ts: the 1354-entry CONTEXT_LIMITS table (65KB) and its
  generation apparatus deleted; the fold returns limit: number | null.
  PRICES untouched (regen verified byte-identical via the reworked
  sync-pricing script).
- scripts/sync-pricing.ts: generates PRICES only; contextWindow leaves
  the priced map, the guard, and the template.
- The dock meter's owner-selected treatment: the activity feed carries
  the limit server-side. catalogContextLimits() (server/model-catalog.ts)
  builds the index over the same keyed providers the picker federates;
  activityFeed() joins it onto every running job (ActivityJob.contextLimit,
  null when the model is missing — the dock reads it off the feed, no
  client-side table, no regression while the UI's catalog-join chunk lands).
- components/activity-dock.tsx: toBlobs reads job.contextLimit (import
  of CONTEXT_LIMITS gone); stats-bar renders usage-only on null limit
  (mechanical interim — UI stream's join chunk follows).
- tests: usage.test.ts pins the no-fallback contract (index hit / absent
  / empty / missing-model -> null); activity-feed.test.ts pins the
  server join (catalog model -> 1048576, unknown -> null, no-usage ->
  null); render pins updated to the interim usage-only render.

tests/render-stats-bar.test.tsx

@@ -50,9 +50,11 @@ describe("stats bar", () => {
 		const html = renderToStaticMarkup(
 			<StatsBar turns={[turn(), turn()]} />,
 		);
-		// last turn's last call: 10k in + 1k out = 11k; pi catalog limit
-		// 1_048_576 → "1M" (tables regenerated from pi-ai's catalog)
-		assert.match(html, /data-testid="stats-context">11k \/ 1M</);
+		// last turn's last call: 10k in + 1k out = 11k. The LIMIT is the
+		// live catalog's — and the bar doesn't hold the index yet (the
+		// catalog join lands with the UI chunk), so the meter renders
+		// USAGE-ONLY (owner amendment: never a fallback window).
+		assert.match(html, /data-testid="stats-context">11k</);
 		// pi catalog price 0.075/0.25 per 1M: each turn 10k×0.075 + 1k×0.25
 		// = $0.001 → two = $0.0020
 		assert.match(html, /data-testid="stats-cost">\$0\.0020</);
@@ -67,8 +69,10 @@ describe("stats bar", () => {
 			<StatsBar turns={[turn({ model: "nope/unknown" })]} />,
 		);
 		assert.match(html, /data-testid="stats-cost">—</);
-		// unknown model also kills the context limit
-		assert.match(html, /data-testid="stats-context">—</);
+		// unknown model: no catalog limit exists, but the footprint is
+		// still an honest reading — usage-only (never "—" theater over
+		// real data, never a fake window)
+		assert.match(html, /data-testid="stats-context">11k</);
 	});
 
 	it("prettyModel strips vendor + date suffix, capitalizes", () => {