feedback5: merge feedback4 (beb0296) — PR #73 (operator battle voices) ported to the split layout (the voice setting into ui/gameLogic/settings.js, the gameLogic.js shim unchanged; onResult and DetailPanel voice stay in screens/game.js, which needed its store import back; the sim's 'engage' in server/sim/ai.js performAttack, still the one battle/combat.js and devices.js call; plan.mjs / fetch-assets.mjs merged with --add-only, extraOperators and moduleTypes; the 干员语音 slider through t() with English); golden: roster / bonds / fields / standins / diy differ only in events.engage, matches unchanged

Ported by hand:
- public/js/ui/gameLogic.js is a re-export shim on feedback5: #73's DEFAULT_SETTINGS / sanitizeSettings `voice`
  hunk went into public/js/ui/gameLogic/settings.js.
- public/js/screens/game.js: MatchScreen still lives there, so #73's onResult (battleRunner 'result' → resultSpeaker /
  resultVoiceSlot) and `voice=${combat}` on the DetailPanel auto-merged in place. feedback5's game.js no longer
  imported `store` (the split moved its other users), so onResult's store.get() would have thrown into its
  try/catch and the 结算 line would never have played: `store` is imported again. `localAsset` stays dropped.
- public/js/ui/settings.js (i18n phase 1): the slider is `label=${t('干员语音')}`, public/i18n/en.json
  "干员语音": "Operator Voices" (next to Music / Sound Effects).
- tools/assets/plan.mjs: buildPlan takes #73's charword / voiceLang / voiceSlots and feedback5's extraOperators /
  moduleTypes; the template has `modules` and audio { bgm, bossBgm, voice, sfx }. `chars` now includes the 自选 picks,
  so the voice loop's comment says so (the next `npm run assets` plans their lines too).
- tools/fetch-assets.mjs: parseArgs keeps --add-only beside --voice-lang / --voice-all.
- data/assets.json: feedback5's manifest plus #73's audio.voice (120 operators, after bossBgm, the plan order);
  stats files +1680 and bytes +42 041 118 as measured on feedback4, voiceChars 120; the hash is recomputed with
  the generator's contentHash. No other entry changed.
- docs/ASSETS.md: the stats line lists modules and voiceChars. DESIGN §21.30 stays where feedback4 put it; SIM.md's
  'engage' line and docs-consistency's §21.30 test auto-merged (game.js / detailPanel.js still hold the pinned code).
- Auto-merged and checked: audio.js, battle/runner.js emit('result'), components.js mic icon, detailPanel.js voice
  prop, shared/protocol.js EV.ENGAGE, server/sim/ai.js, tools/assets/audio.mjs / cache.mjs, #73's tests.

Where #73 met feedback5 work:
- 补位: a chess fielded as its stand-in shows the stand-in in the detail card, and audio.js keys battle lines by
  UnitInfo spine (the stand-in's model). The 选中干员 line now takes detail.standIn.charId first, so the stand-in
  speaks, not the operator it replaces (test/ui/standin-ui.test.js pins it). A 自选 record is already the pick's.
- The sim's 'engage': stand-in and 自选 units attack through the same performAttack, so it fires for them as well.

Golden regenerated: every moved scenario differs only in events.engage (the new event's count; no gameplay change),
proven by a field-path diff against feedback5:
- roster: all 49; bonds: all 46; fields: all 22; standins: all 10 (the stand-ins engage).
- diy: 101 of 109. Unmoved: diy-010/011/012/092/093 (闪灵, 夜莺, 凯尔希 squads: they only heal, and a heal never
  engages) and diy-077 (薇薇安娜), diy-080/081 (赫德雷), whose picks make no attack in those battles (already so on
  feedback5).
- matches: unchanged.

test/sim/battle.test.js

@@ -392,6 +392,24 @@ test('snapshot / event wire format (DESIGN §8.2)', () => {
   JSON.stringify(snap); // serialisable
 });
 
+test('one ENGAGE per unit, on its first attack that hits an enemy (the client\'s 行动开始 voice)', () => {
+  const h = makeBattle({
+    defs: { chess: { t_guard: guard({ stats: { atk: 100, maxHp: 5000 } }) }, enemies: { enemy_walker: walker({ atk: 100, hp: 3000 }) } },
+    units: [{ chessId: 't_guard', row: 9, col: 5 }],
+    enemies: [{ key: 'enemy_walker' }], content: 'generic', fieldId: 'n:p1',
+  });
+  h.run(60); // the walker (0.5 tiles/s) reaches the guard at ~9 s and is attacked from then on
+  const id = h.unit('t_guard').id;
+  const engage = h.eventsOf(EV.ENGAGE);
+  assert.equal(engage.length, 1, 'one event for the whole battle');
+  assert.deepEqual(engage[0], ['engage', id]);
+  // it is emitted at the unit's first attack on an enemy — an earlier 命中的攻击 is impossible
+  const first = h.events.findIndex((e) => e[0] === 'engage');
+  const earlierAtk = h.events.slice(0, first).findIndex((e) => e[0] === 'atk' && e[1] === id);
+  assert.equal(earlierAtk, -1, 'no attack of that unit precedes it');
+  assert.ok(h.events.slice(first).some((e) => e[0] === 'atk' && e[1] === id), 'the attack it belongs to');
+});
+
 test('determinism: same seed ⇒ identical result and event stream; different seed may differ', () => {
   const ds = getDefaultSource();
   const tpl = ds.getWave('act1autochess_05');