feat(custom-field): tambahkan fitur custom field

- Menambahkan model CustomField dengan atribut mass assignable.
- Membuat request validation untuk custom field.
- Menambahkan route dan breadcrumb untuk custom field.
- Membuat migration untuk tabel custom_fields.
- Menambahkan export functionality untuk custom field.
- Membuat view untuk menambah dan mengedit custom field.

app/Http/Requests/CustomFieldRequest.php

@@ -0,0 +1,33 @@
+<?php
+
+namespace Modules\Lpj\Http\Requests;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class CustomFieldRequest extends FormRequest
+{
+    /**
+     * Get the validation rules that apply to the request.
+     */
+    public function rules(): array
+    {
+        return [
+            'name' => 'required|max:255',
+            'type' => 'required|in:text,select,radio,checkbox',
+        ];
+    }
+
+    /**
+     * Determine if the user is authorized to make this request.
+     */
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    public function prepareValidationData($data){
+        if(!$this->type){
+            $this->merge(['type' => 'text']);
+        }
+    }
+}