Update user registration email format, remove unused SMS helper function, and adjust database migration for user meta column

app/Modules/OTPVerification/Models/OTPVerification.php

@@ -0,0 +1,25 @@
+<?php
+
+namespace App\Modules\OTPVerification\Models;
+
+use Illuminate\Database\Eloquent\Model;
+
+/**
+ * @property int $id
+ * @property string $username
+ * @property string $code
+ * @property Carbon $created_at
+ * @property Carbon $updated_at
+ */
+class OTPVerification extends Model
+{
+    /**
+     * The table associated with the model.
+     */
+    protected $table = 'otp_verifications';
+
+    /**
+     * The attributes that are mass assignable.
+     */
+    protected $fillable = ['username', 'code'];
+}