feat(hud): Cyber HUD theme with GPU contact sonar (#706)

Add the opt-in Cyber HUD layout with coordinated map and cockpit panel
styling, GPU-only contact sonar (rings, range, power, opacity, sector) with
native-rendering fallback, and set_cyber_sonar voice controls. Sonar visual
style inspired by kk376's tactical naval sonar (#214).

Co-authored-by: Sameh Khamis <[email protected]>
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

src/keySetup.test.mjs

@@ -4,8 +4,43 @@ import {
   collectKeyUpdates,
   keySetupChipLabel,
   stripKeylessBasemapFromHash,
+  bindKeySetupPlacement,
 } from './keySetup.js';
 
+test('setup placement moves the same button only in Cyber and disconnects on teardown', () => {
+  const home = {};
+  const chip = { parentNode: home, hidden: true };
+  const root = { parentNode: home, before: (node) => { node.parentNode = home; } };
+  let moves = 0;
+  const toolbar = { append: (node) => { moves++; node.parentNode = toolbar; } };
+  const theme = { dataset: { uiTheme: 'tactical' } };
+  let notify, disconnected = false;
+  class Observer {
+    constructor(callback) { notify = callback; }
+    observe(target, options) {
+      assert.equal(target, theme);
+      assert.deepEqual(options.attributeFilter, ['data-ui-theme']);
+    }
+    disconnect() { disconnected = true; }
+  }
+  const dispose = bindKeySetupPlacement({
+    documentElement: theme,
+    getElementById: () => toolbar,
+    defaultView: { MutationObserver: Observer },
+  }, chip, root);
+  assert.equal(chip.parentNode, home);
+  for (const variant of ['cyber', 'operator', 'cyber', 'minimal']) {
+    theme.dataset.uiTheme = variant;
+    notify();
+    assert.equal(chip.parentNode, variant === 'cyber' ? toolbar : home);
+    notify();
+  }
+  assert.equal(moves, 2, 'identical theme sync does not reparent again');
+  assert.equal(chip.hidden, true, 'placement cannot reveal a retired button');
+  dispose();
+  assert.equal(disconnected, true);
+});
+
 test('the chip counts what is missing, and retires the count at zero', () => {
   assert.equal(keySetupChipLabel({ setCount: 0, total: 8 }), 'POWER UP · 8 KEYS WAITING');
   assert.equal(keySetupChipLabel({ setCount: 7, total: 8 }), 'POWER UP · 1 KEY WAITING');