Combine Rules and Admin corner links into one upper-right menu

Replace the fixed Rules link (upper-left) and the creator-only Admin
link (upper-right) with a single collapsible ☰ Menu in the upper right,
leaving the event log alone in its corner. CornerMenu always lists the
Rules link; pages can contribute context-specific entries through the
extraMenuLinks store, which Dashboard uses for the creator-only Admin
link. This gives future misc sub-pages a home without eating more
screen corners.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

frontend/src/pages/Dashboard.svelte

@@ -1,7 +1,8 @@
 <script>
     import { onMount, onDestroy } from 'svelte';
     import { apiRequest } from '../lib/api';
-    
+    import { extraMenuLinks } from '../lib/menu';
+
     import LobbyPhase from '../components/LobbyPhase.svelte';
     import CharacterCreationPhase from '../components/CharacterCreationPhase.svelte';
     import SceneSetupPhase from '../components/SceneSetupPhase.svelte';
@@ -34,8 +35,16 @@
         intervalId = setInterval(fetchState, 2000);
     });
 
+    // Surface the creator-only Admin link in the corner menu
+    $: extraMenuLinks.set(
+        state?.player?.is_creator
+            ? [{ label: '🛠️ Admin', href: `#/game/${gameId}/admin`, title: 'Open the Admin Panel' }]
+            : []
+    );
+
     onDestroy(() => {
         if (intervalId) clearInterval(intervalId);
+        extraMenuLinks.set([]);
     });
 </script>
 
@@ -65,10 +74,6 @@
     </div>
 
     <EventLog {state} />
-
-    {#if state.player.is_creator}
-        <a class="admin-corner-link" href="#/game/{gameId}/admin" title="Open the Admin Panel">🛠️ Admin</a>
-    {/if}
 {:else if !error}
     <div class="loading-container">
         <p>Loading game state...</p>
@@ -76,24 +81,6 @@
 {/if}
 
 <style>
-    .admin-corner-link {
-        position: fixed;
-        top: 12px;
-        right: 16px;
-        z-index: 1001;
-        padding: 6px 14px;
-        border-radius: 16px;
-        background: rgba(10, 15, 25, 0.9);
-        border: 1px solid var(--gold, #d4af37);
-        color: var(--gold, #d4af37);
-        font-size: 0.85rem;
-        font-weight: 700;
-        text-decoration: none;
-        font-family: var(--font-heading);
-    }
-    .admin-corner-link:hover {
-        background: rgba(212, 175, 55, 0.15);
-    }
     .loading-container {
         display: flex;
         justify-content: center;