Initial commit: private Texas Hold'em ring game site (lobby + table stub)

- 6-digit access key gate with long-lived HttpOnly cookie, brute-force limits
- Lobby with saved player name and live table list
- Table creation (name, starting stack, blinds, blind timer)
- Table play screen stub (seats, button/SB/BB, phase, blinds, timer)
- Security hardening: strict CSP, origin checks, host pinning, input sanitizing

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

public/create.html

@@ -0,0 +1,60 @@
+<!doctype html>
+<html lang="ja">
+<head>
+  <meta charset="utf-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1, viewport-fit=cover">
+  <meta name="theme-color" content="#24493b">
+  <meta name="robots" content="noindex, nofollow">
+  <title>テーブル作成 - Hold'em Night</title>
+  <link rel="stylesheet" href="/assets/style.css">
+</head>
+<body>
+  <main class="wrap">
+    <div class="topbar">
+      <a class="icon-btn" href="/" aria-label="戻る">←</a>
+      <h1>テーブルを作成</h1>
+    </div>
+
+    <form id="form" novalidate>
+      <label for="table-name">テーブル名</label>
+      <div class="row">
+        <input id="table-name" type="text" maxlength="24" required>
+        <button type="button" class="icon-btn" id="reroll" aria-label="別の名前にする">🎲</button>
+      </div>
+
+      <label for="stack">開始スタック</label>
+      <input id="stack" type="number" inputmode="numeric" min="10" step="1" value="1000">
+
+      <div class="label">開始ブラインド（SB / BB）</div>
+      <div class="row">
+        <input id="sb" type="number" inputmode="numeric" min="1" step="1" aria-label="スモールブラインド">
+        <span class="slash">/</span>
+        <input id="bb" type="number" inputmode="numeric" min="1" step="1" aria-label="ビッグブラインド">
+      </div>
+      <div class="hint" id="blind-hint">スタックに合わせて自動設定（BB ≒ スタックの1/100）</div>
+
+      <div class="switch-row">
+        <span>ブラインドタイマー</span>
+        <label class="switch">
+          <input id="timer" type="checkbox" aria-label="ブラインドタイマー">
+          <span></span>
+        </label>
+      </div>
+
+      <label for="interval">インターバル</label>
+      <div class="unit-input">
+        <input id="interval" type="number" inputmode="numeric" min="1" max="240" step="1" value="10" disabled>
+        <span class="unit">min</span>
+      </div>
+      <div class="schedule" id="schedule" hidden></div>
+
+      <div class="error-text" id="error"></div>
+      <button class="btn btn-orange btn-block mt-8" id="submit" type="submit">テーブルを作成</button>
+    </form>
+  </main>
+
+  <script src="/assets/common.js"></script>
+  <script src="/assets/blinds.js"></script>
+  <script src="/assets/create.js"></script>
+</body>
+</html>