feat: Buat enum sign_up_method.dart beserta dengan extension function-nya

Author: CoderJava

lib/core/util/enum/sign_up_method.dart

@@ -0,0 +1,26 @@
+enum SignUpMethod {
+  manual,
+  auto,
+}
+
+extension SignUpMethodExtension on SignUpMethod {
+  String toValue() {
+    switch (this) {
+      case SignUpMethod.manual:
+        return 'manual_approval';
+      case SignUpMethod.auto:
+        return 'auto_approval';
+      default:
+        return '';
+    }
+  }
+
+  static SignUpMethod? parseString(String value) {
+    if (value.contains('manual')) {
+      return SignUpMethod.manual;
+    } else if (value.contains('auto')) {
+      return SignUpMethod.auto;
+    }
+    return null;
+  }
+}