feat: add Reverb realtime messaging

app/Http/Requests/Messaging/StoreConversationRequest.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace App\Http\Requests\Messaging;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class StoreConversationRequest extends FormRequest
+{
+    public function authorize(): bool
+    {
+        return $this->user() !== null;
+    }
+
+    public function rules(): array
+    {
+        return [
+            'type' => 'required|in:direct,group',
+            'recipient_id' => 'required_if:type,direct|integer|exists:users,id',
+            'participant_ids' => 'required_if:type,group|array|min:2',
+            'participant_ids.*' => 'integer|exists:users,id',
+            'title' => 'required_if:type,group|nullable|string|max:120',
+            'body' => 'required|string|max:5000',
+            'client_temp_id' => 'nullable|string|max:120',
+        ];
+    }
+}