fix: resolve PSR-4 autoloading and test failures

- Add proper Tests\ namespace to all test classes in tests/Feature and tests/Unit
  - Split RemainingModelsTest.php into separate files (PSR-4 compliance)
  - Create missing factories: MetaFactory, RemoteEmailFactory
  - Add HasFactory trait to RemoteEmail model
  - Add missing ReflectionClass imports to test files
  - Fix mass assignment issues in Meta and RemoteEmail models
  - Override database connection for RemoteEmail in testing environment
  - Fix DateTime comparison precision issues in tests

app/Models/Meta.php

@@ -8,6 +8,11 @@ use Illuminate\Database\Eloquent\Model;
 class Meta extends Model {
     use HasFactory;
 
+    protected $fillable = [
+        'key',
+        'value',
+    ];
+
     public function incrementMeta($value = 1) {
         $this->value = $this->value + $value;
         $this->save();

app/Models/RemoteEmail.php

@@ -2,14 +2,43 @@
 
 namespace App\Models;
 
+use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Support\Facades\Validator;
 
 class RemoteEmail extends Model
 {
-    protected $connection = 'mysql_remote';
+    use HasFactory;
     protected $table = 'emails';
 
+    public function getConnectionName()
+    {
+        if (app()->environment('testing')) {
+            return config('database.default');
+        }
+
+        return 'mysql_remote';
+    }
+
+    
+    protected $fillable = [
+        'message_id',
+        'subject',
+        'from_name',
+        'from_email',
+        'to',
+        'body_html',
+        'body_text',
+        'is_seen',
+        'timestamp',
+    ];
+
+    protected $casts = [
+        'to' => 'array',
+        'is_seen' => 'boolean',
+        'timestamp' => 'datetime',
+    ];
+
     public static function fetchEmailFromDB($email)
     {
         $validator = Validator::make(['email' => $email], [