feat(voice): voice core — honest layer reach, spoken summary with on-screen card, narration, point-and-ask

- Voice layer manifest (src/voice/layerManifest.js) generates the layer enums,
  aliases and analyst field hints; a test fails when a catalog layer has no entry.
- analyst_query validates fields, operators, units, values and scopes, counts up
  to 250,000 loaded records per layer, reports complete/partial/unanswered, tells
  LAYER_OFF / NOT_READY / FEED_UNAVAILABLE apart from zero, refuses mismatched
  follow-ups and never lets a superseded query replace follow-up memory. Seven
  more layers expose analyst records.
- Tool results carry a code-built say line and a display card; the voice card in
  the mic control shows captions, plan steps and the result
  (src/voice/resultDisplay.js is the one adapter). Slow tools narrate their
  current step out of band; holding Space while the assistant talks cuts it off.
  Turn spans go to the debug log; caption transcription is metered; the log
  omits what was said unless GEV_VOICE_LOG_CONTENT=1.
- Point and ask: the Space-down pointer snapshot resolves "this", "that one" and
  "around here" through 'pointer' targets, and "the second one" through
  referent:n from the last numbered list.
- Prompt states each policy once (instructions + tools 48.5k -> 46.7k chars).
- Voice benchmark harness (scripts/qa-voice-bench.mjs, scripts/voice-bench/)
  shares its phrase table and grading with scripts/qa-voice-routing.mjs.

scripts/voice-bench/stub.mjs

@@ -0,0 +1,21 @@
+/**
+ * Stub tool results fed back to the model after each call. Pure.
+ *
+ * core suite: the neutral `{ ok:true }` stub qa-voice-routing has always
+ *   used, so continuations behave exactly as in that harness.
+ * coverage suite: the same stub, except a call whose arguments violate the
+ *   tool schema gets `{ ok:false, error }` — what the app's runner returns
+ *   for an unknown layer id — so the model's follow-up words can be judged
+ *   for honesty.
+ */
+import { validateCall } from './grade.mjs';
+
+export const STUB_OK = Object.freeze({ ok: true, note: 'qa-harness stub result' });
+
+export function stubResult(suite, c, tools) {
+  if (suite === 'coverage') {
+    const errors = validateCall(tools, c);
+    if (errors.length) return { ok: false, error: `Invalid arguments: ${errors.join('; ')}` };
+  }
+  return { ...STUB_OK };
+}