Add CPU opponents and a table type selector (cash only / friends / CPU)

- Create screen: choose キャッシュオンリー (real cards, chips only), 友人戦
  (server deals and settles) or CPU戦 (友人戦 plus 1–8 CPU players); replaces
  the card toggle. The lobby shows each table's type
- Poker AI written from scratch (server/ai.js, no libraries): fast 7-card
  evaluator (checked against bestHand), Monte Carlo equity, and decisions from
  hand rank, pot odds, raise count, opponents and a per-CPU style (aggression,
  bluff rate); continuation bets via the last aggressor. It never sees other
  players' hole cards
- CPU seats: think time of 0.7–1.8s (faster when no human is left in the hand),
  automatic rebuy, never the host, no new hand unless a human is playing,
  re-think after pause
- Play UI: robot avatars and a "考えています…" status for CPU turns
- Tests for the evaluator, equity, legality of AI actions and CPU tables

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

public/assets/create.js

@@ -16,8 +16,8 @@
   const timerInput = $('timer');
   const intervalInput = $('interval');
   const scheduleEl = $('schedule');
-  const cardsInput = $('cards');
-  const cardsHint = $('cards-hint');
+  const modeHint = $('mode-hint');
+  const cpuOptions = $('cpu-options');
   const blindHint = $('blind-hint');
   const errorEl = $('error');
   const submitBtn = $('submit');
@@ -68,16 +68,23 @@
       .join('');
   }
 
-  function updateCardsHint() {
-    cardsHint.textContent = cardsInput.checked
-      ? 'オン: 各自のスマホに手札が配られ、勝敗とポットの分配は自動'
-      : 'オフ: 実物のカードで遊び、ショーダウンの勝者はホストが選ぶ';
+  const MODE_HINTS = {
+    chips: '実物のカードで遊び、サイトはチップだけを管理。ショーダウンの勝者はホストが選ぶ',
+    friends: '各自のスマホに手札が配られ、勝敗とポットの分配は自動',
+    cpu: 'CPU と対戦（友達も空いている席に参加できる）。カードの配布・勝敗の判定は自動',
+  };
+  const radioValue = (name) => (form.querySelector(`input[name="${name}"]:checked`) || {}).value;
+
+  function updateMode() {
+    const mode = radioValue('mode');
+    modeHint.textContent = MODE_HINTS[mode] || '';
+    cpuOptions.hidden = mode !== 'cpu';
   }
 
   function refresh() {
     updateHint();
     updateSchedule();
-    updateCardsHint();
+    updateMode();
   }
 
   stackInput.addEventListener('input', () => {
@@ -100,7 +107,7 @@
   });
   timerInput.addEventListener('change', refresh);
   intervalInput.addEventListener('input', refresh);
-  cardsInput.addEventListener('change', refresh);
+  form.querySelectorAll('input[type="radio"]').forEach((el) => el.addEventListener('change', refresh));
   $('reroll').addEventListener('click', suggestName);
 
   function validate() {
@@ -138,7 +145,8 @@
         bigBlind: int(bbInput),
         blindTimerEnabled: timerInput.checked,
         blindIntervalMin: int(intervalInput),
-        cardsEnabled: cardsInput.checked,
+        mode: radioValue('mode'),
+        cpuCount: Number(radioValue('cpu-count')),
         token: Store.token,
       });
       location.href = '/table/' + encodeURIComponent(id);

public/assets/lobby.js

@@ -36,6 +36,8 @@
     if (btn && requireName()) location.href = '/table/' + encodeURIComponent(btn.dataset.join);
   });
 
+  const MODE_LABEL = { chips: '💰 キャッシュオンリー', friends: '🃏 友人戦', cpu: '🤖 CPU戦' };
+
   function phaseBadge(t) {
     if (t.paused) return '<span class="badge paused">PAUSED</span>';
     if (t.phase === 'WAITING') return '<span class="badge">WAITING</span>';
@@ -61,7 +63,7 @@
                 <span>開始 <b>${chips(t.startingStack)}</b></span>
                 <span class="gold">Lv.${t.level} <b class="gold">${chips(t.smallBlind)}/${chips(t.bigBlind)}</b></span>
                 <span>${timer}</span>
-                ${t.cardsEnabled ? '<span>🃏 カードあり</span>' : ''}
+                <span>${MODE_LABEL[t.mode] || ''}</span>
               </div>
             </div>
             <button class="btn btn-blue btn-sm" data-join="${esc(t.id)}" ${full ? 'title="満席（観戦のみ）"' : ''}>

public/assets/style.css

@@ -255,6 +255,29 @@ input.invalid { border-color: var(--red); }
 .switch input:checked + span::before { transform: translateX(22px); background: #fff; }
 .switch input:focus-visible + span { outline: 2px solid var(--gold); }
 
+/* 選択肢を横に並べたラジオボタン（テーブルの種類・CPU の人数） */
+.segmented { display: grid; grid-auto-flow: column; grid-auto-columns: 1fr; gap: 6px; }
+.segmented label { margin: 0; display: block; color: var(--text); }
+.segmented input { position: absolute; opacity: 0; width: 0; height: 0; }
+.segmented span {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  text-align: center;
+  min-height: 52px;
+  padding: 6px 4px;
+  border-radius: 12px;
+  background: var(--input);
+  border: 2px solid transparent;
+  font-weight: 800;
+  font-size: 14px;
+  line-height: 1.2;
+  cursor: pointer;
+}
+.segmented input:checked + span { background: rgba(246, 199, 68, 0.15); border-color: var(--gold); color: var(--gold); }
+.segmented input:focus-visible + span { outline: 2px solid var(--gold); outline-offset: 2px; }
+.segmented.numbers span { min-height: 40px; font-size: 15px; }
+
 .unit-input { position: relative; }
 .unit-input input { padding-right: 56px; }
 .unit-input .unit {
@@ -400,6 +423,7 @@ body.table-page {
 }
 .avatar svg { width: 28px; height: 28px; fill: #fff; }
 .seat.me .avatar { background: #d35400; border-color: var(--gold); }
+.seat.bot .avatar { background: #3d4a6b; border-color: #8fa2d6; }
 .seat.offline .avatar { opacity: 0.45; }
 .nameplate {
   margin-top: -10px;

public/assets/table.js

@@ -9,6 +9,8 @@
 
   const AVATAR_SVG =
     '<svg viewBox="0 0 24 24" aria-hidden="true"><circle cx="12" cy="8" r="4.5"/><path d="M3 21c0-4.4 4-7.5 9-7.5s9 3.1 9 7.5z"/></svg>';
+  const BOT_SVG =
+    '<svg viewBox="0 0 24 24" aria-hidden="true"><rect x="11" y="1.5" width="2" height="3.5" rx="1"/><circle cx="12" cy="1.8" r="1.6"/><path d="M5 7.5A2.5 2.5 0 0 1 7.5 5h9A2.5 2.5 0 0 1 19 7.5v7a2.5 2.5 0 0 1-2.5 2.5h-9A2.5 2.5 0 0 1 5 14.5zM9 9.2a1.6 1.6 0 1 0 0 3.2 1.6 1.6 0 0 0 0-3.2zm6 0a1.6 1.6 0 1 0 0 3.2 1.6 1.6 0 0 0 0-3.2zM2 9.5h2v4H2zm18 0h2v4h-2zM7 18.5h10a3 3 0 0 1 3 3V23H4v-1.5a3 3 0 0 1 3-3z"/></svg>';
   // U+FE0E: iOS で絵文字として描画されないように
   const SUIT_SYMBOL = { s: '♠︎', h: '♥︎', d: '♦︎', c: '♣︎' };
   const ACTION_LABEL = { FOLD: 'Fold', CHECK: 'Check', CALL: 'Call', BET: 'Bet', RAISE: 'Raise', ALLIN: 'All-in' };
@@ -234,6 +236,7 @@
       .map((p, idx) => {
         const classes = ['seat'];
         if (p.seat === s.mySeat) classes.push('me');
+        if (p.bot) classes.push('bot');
         if (!p.connected) classes.push('offline');
         if (p.inHand && p.folded) classes.push('folded');
         if (s.toAct === p.seat) classes.push('turn');
@@ -273,7 +276,7 @@
 
         return `
           <div class="${classes.join(' ')}">
-            <div class="avatar">${AVATAR_SVG}${markers}${cards}</div>
+            <div class="avatar">${p.bot ? BOT_SVG : AVATAR_SVG}${markers}${cards}</div>
             <div class="nameplate">
               ${tag}
               <div class="pname">${esc(p.name)}</div>
@@ -324,7 +327,10 @@
     else if (m.canRebuy) status = 'チップがなくなりました';
     else if (o) status = o.canCheck ? 'あなたの番です' : `あなたの番です（コール ${chips(o.toCall)}）`;
     else if (awaiting) status = m.canAward ? 'カードを見せ合って、勝った人を選んでください' : 'ホストが勝者を選んでいます';
-    else if (h && !h.finished && s.toAct != null) status = `${nameOf(s.toAct)} の番です`;
+    else if (h && !h.finished && s.toAct != null) {
+      const actor = s.seats[s.toAct];
+      status = actor && actor.bot ? `${actor.name}（CPU）が考えています…` : `${nameOf(s.toAct)} の番です`;
+    }
     else if (h && !h.finished && h.runout) status = 'オールイン — 残りのカードをめくります';
     else if (h && !h.finished && !seat.inHand) status = '次のハンドから参加します';
     else if (h && h.finished) status = '次のハンドを準備中…';