Add restaurant/café mode: floor, open tabs, and kitchen display (Phase 1)

Gated by a per-location service_style (retail | restaurant). Restaurant mode adds:
- Floor screen with tables (areas, seats, status) — tap a free table to open a
  dine-in tab; takeaway/counter orders open from the same screen.
- Open tickets (tabs): a sale stays pending while items are added; lines persist
  as you go (posTicket Alpine component posts each change to the server).
- Send-to-kitchen fires un-sent lines; a polling Kitchen Display (KDS) shows
  active tickets and bumps items queued → preparing → ready → served.
- Settlement reuses the existing cash / Ladill Pay flow; paying closes the tab
  and frees the table (PosSaleService::closeTicket, wired into both pay paths).
- Settings gains the mode toggle and a tables manager.

Schema is additive (new pos_tables; service_style on locations; order/kitchen
columns on sales + lines). Retail flow is untouched. Sidebar surfaces Floor +
Kitchen only in restaurant mode. New PosRestaurantTest covers the dine-in
lifecycle end to end; suite green (10 passed).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/Models/PosLocation.php

@@ -8,18 +8,33 @@ use Illuminate\Database\Eloquent\Relations\HasMany;
 
 class PosLocation extends Model
 {
+    public const STYLE_RETAIL = 'retail';
+
+    public const STYLE_RESTAURANT = 'restaurant';
+
     protected $fillable = [
         'owner_ref',
         'name',
         'currency',
+        'service_style',
         'receipt_footer',
     ];
 
+    public function isRestaurant(): bool
+    {
+        return $this->service_style === self::STYLE_RESTAURANT;
+    }
+
     public function products(): HasMany
     {
         return $this->hasMany(PosProduct::class, 'location_id');
     }
 
+    public function tables(): HasMany
+    {
+        return $this->hasMany(PosTable::class, 'location_id');
+    }
+
     public function sales(): HasMany
     {
         return $this->hasMany(PosSale::class, 'location_id');