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  follow-ups and never lets a superseded query replace follow-up memory.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.

src/voice/pointerPick.js

@@ -0,0 +1,61 @@
+import * as Cesium from 'cesium';
+import { resolvePickedContext } from '../data/pickedContext.js';
+import { cameraPoseKey } from './pointerContext.js';
+import * as defaultAnnotationResolver from '../annotations/annotationResolver.js';
+
+/** "Around here" radius as a share of camera height, clamped to sane bounds. */
+export function pointerRadiusKm(cameraHeightM) {
+  const heightKm = Number(cameraHeightM) / 1000;
+  if (!Number.isFinite(heightKm) || heightKm <= 0) return 50;
+  return Math.round(Math.min(400, Math.max(5, heightKm * 0.75)));
+}
+
+/**
+ * The Cesium side of point-and-ask: one entity pick and one depth-aware world
+ * pick at canvas CSS pixels. Called lazily by the pointer tracker (dwell and
+ * snapshot only), never per mouse move.
+ * @param {object} options
+ * @param {object} options.viewer Cesium viewer.
+ * @param {object} [options.dataManager] Layer lifecycle.
+ * @param {Function} [options.pickWorldFromScreen] Normalized-pixel world pick.
+ * @returns {(x: number, y: number) => {entity: object|null, ground: object|null, radiusKm: number}|null}
+ */
+export function createPointerPicker({
+  viewer,
+  dataManager = null,
+  pickWorldFromScreen = defaultAnnotationResolver.pickWorldFromScreen,
+}) {
+  return function pickPointer(x, y) {
+    const scene = viewer?.scene;
+    const canvas = scene?.canvas;
+    if (!scene || !canvas) return null;
+    const width = canvas.clientWidth || canvas.width || 0;
+    const height = canvas.clientHeight || canvas.height || 0;
+    if (!width || !height) return null;
+    let picked = null;
+    try {
+      picked = scene.pick(new Cesium.Cartesian2(x, y));
+    } catch {
+      picked = null;
+    }
+    const entity = resolvePickedContext(picked, { dataManager });
+    let ground = null;
+    try {
+      const hit = pickWorldFromScreen(viewer, x / width, y / height);
+      if (hit && Number.isFinite(hit.lat) && Number.isFinite(hit.lon))
+        ground = {
+          lat: hit.lat,
+          lon: hit.lon,
+          heightM: Number.isFinite(hit.height) ? Math.round(hit.height) : null,
+        };
+    } catch {
+      ground = null;
+    }
+    return {
+      entity,
+      ground,
+      radiusKm: pointerRadiusKm(viewer.camera?.positionCartographic?.height),
+      cameraKey: cameraPoseKey(viewer),
+    };
+  };
+}