fix: resolve PHPStan static analysis warnings

app/Models/TicketMessage.php

@@ -3,7 +3,20 @@
 namespace App\Models;
 
 use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
 
+/**
+ * App\Models\TicketMessage
+ *
+ * @property int $id
+ * @property int $ticket_id
+ * @property int $user_id
+ * @property string $message
+ * @property \Illuminate\Support\Carbon $created_at
+ * @property \Illuminate\Support\Carbon $updated_at
+ * @property-read \App\Models\Ticket $ticket 关联的工单
+ * @property-read bool $is_me 当前消息是否由工单发起人发送
+ */
 class TicketMessage extends Model
 {
     protected $table = 'v2_ticket_message';
@@ -13,4 +26,22 @@ class TicketMessage extends Model
         'created_at' => 'timestamp',
         'updated_at' => 'timestamp'
     ];
+
+    protected $appends = ['is_me'];
+
+    /**
+     * 关联的工单
+     */
+    public function ticket(): BelongsTo
+    {
+        return $this->belongsTo(Ticket::class, 'ticket_id', 'id');
+    }
+
+    /**
+     * 判断消息是否由工单发起人发送
+     */
+    public function getIsMeAttribute(): bool
+    {
+        return $this->ticket->user_id === $this->user_id;
+    }
 }