feat: grid layout, global claim/qty toggles, admin access link, swaddle image

- Public wishlist now renders as responsive 3-col grid instead of list
- Subtitle supports line breaks (whitespace-pre-line)
- claimingEnabled and showQuantity moved to global site settings (not per-item); toggled in admin Configurações panel; claim API enforces server-side
- Admin dashboard shows admin access link with copy button
- Settings API exposes and persists the two new boolean settings

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/api/public/items/[id]/claim/route.ts

@@ -1,6 +1,6 @@
 import { NextRequest, NextResponse } from 'next/server';
 import { and, eq, ne, sql } from 'drizzle-orm';
-import { db, wishlistItems, wishlists, itemClaims, guests } from '@/lib/db';
+import { db, wishlistItems, wishlists, itemClaims, guests, settings } from '@/lib/db';
 import { getGuestFromRequest } from '@/lib/auth/tokens';
 
 export async function POST(
@@ -26,6 +26,11 @@ export async function POST(
     if (wl.length === 0) return NextResponse.json({ error: 'Wishlist not found' }, { status: 404 });
     if (!wl[0].isPublic) return NextResponse.json({ error: 'This wishlist is private' }, { status: 403 });
 
+    const claimingSetting = await db.select().from(settings).where(eq(settings.key, 'claimingEnabled')).limit(1);
+    if (claimingSetting[0]?.value === 'false') {
+      return NextResponse.json({ error: 'Reservas desativadas' }, { status: 403 });
+    }
+
     // Atomically check remaining quantity and upsert the claim inside a synchronous
     // transaction to prevent race conditions (better-sqlite3 is synchronous).
     type TxResult = { ok: true } | { ok: false; remaining: number };