Fix queue handoff so tickets keep their number across services.

Handoff now frees the counter, ends the service session, and requeues
the same ticket for the next department — critical for hospital flows
like doctor → lab.

Co-authored-by: Cursor <cursoragent@cursor.com>

app/Models/TicketTransfer.php

@@ -0,0 +1,54 @@
+<?php
+
+namespace App\Models;
+
+use App\Models\Concerns\BelongsToOwner;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+
+class TicketTransfer extends Model
+{
+    use BelongsToOwner;
+
+    protected $table = 'queue_ticket_transfers';
+
+    public $timestamps = false;
+
+    protected $fillable = [
+        'owner_ref',
+        'ticket_id',
+        'from_service_queue_id',
+        'to_service_queue_id',
+        'from_counter_id',
+        'reason',
+        'transferred_by',
+        'transferred_at',
+    ];
+
+    protected function casts(): array
+    {
+        return [
+            'transferred_at' => 'datetime',
+        ];
+    }
+
+    public function ticket(): BelongsTo
+    {
+        return $this->belongsTo(Ticket::class, 'ticket_id');
+    }
+
+    public function fromQueue(): BelongsTo
+    {
+        return $this->belongsTo(ServiceQueue::class, 'from_service_queue_id');
+    }
+
+    public function toQueue(): BelongsTo
+    {
+        return $this->belongsTo(ServiceQueue::class, 'to_service_queue_id');
+    }
+
+    public function fromCounter(): BelongsTo
+    {
+        return $this->belongsTo(Counter::class, 'from_counter_id');
+    }
+}