Add a settings page for profit display and default stack

- Per-device toggle to hide your own net and the net ranking at tables
- Default starting stack set in settings; creating a table saves the
  stack, SB and BB used as the next defaults
- Number fields on create and settings select all on focus

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

public/assets/table.js

@@ -437,8 +437,9 @@
     const o = m.options;
 
     Fluid.countTo($('my-stack'), m.stack, chips);
-    const net = m.net;
-    $('my-net').textContent = `収支 ${net > 0 ? '+' : net < 0 ? '−' : '±'}${chips(Math.abs(net))}`;
+    // 収支は設定で消せる（この端末だけ）
+    const net = Store.showNet ? m.net : null;
+    $('my-net').textContent = net == null ? '' : `収支 ${net > 0 ? '+' : net < 0 ? '−' : '±'}${chips(Math.abs(net))}`;
     $('my-net').className = net > 0 ? 'plus' : net < 0 ? 'minus' : '';
     $('my-bet').textContent = seat.inHand && seat.bet > 0 ? `ベット中 ${chips(seat.bet)}` : '';
     $('my-hand').textContent = (seat.inHand && seat.handName) || '';
@@ -642,8 +643,11 @@
     net: '収支 = 持っているチップ − バイインの合計（リバイを含む）',
   };
 
+  // 収支を表示しない設定のときはスタック順だけ
+  const rankMode = () => (Store.showNet ? rankBy : 'stack');
+
   function rankingEntries(s) {
-    const key = rankBy === 'net' ? 'net' : 'held';
+    const key = rankMode() === 'net' ? 'net' : 'held';
     const list = s.seats.filter(Boolean).sort((a, b) => b[key] - a[key] || a.seat - b.seat);
     let rank = 0;
     return list.map((p, i) => {
@@ -694,7 +698,7 @@
       const sub = [p.seat === s.mySeat && 'あなた', p.bot && 'CPU', p.sittingOut && '離席中', !p.connected && 'オフライン']
         .filter(Boolean)
         .join(' ・ ');
-      const net = rankBy === 'net';
+      const net = rankMode() === 'net';
       patch(
         el,
         `<span class="rank-no${rank <= 3 ? ` top-${rank}` : ''}">${rank}</span>` +
@@ -712,7 +716,8 @@
       rankRows.delete(seat);
     }
     slideFrom(before); // 順位が変わった行は元の位置から滑らせる
-    $('ranking-note').textContent = RANK_NOTE[rankBy];
+    $('ranking-tabs').hidden = !Store.showNet;
+    $('ranking-note').textContent = RANK_NOTE[rankMode()];
     if (!s.seats.some(Boolean)) listEl.innerHTML = '<li class="empty">まだ誰も座っていません</li>';
   }