feat: add UserResource with is_admin toggle and delete

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

database/migrations/2026_04_04_131727_add_postcode_to_users_table.php

@@ -0,0 +1,28 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        Schema::table('users', function (Blueprint $table) {
+            $table->string('postcode', 8)->nullable()->after('is_admin');
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::table('users', function (Blueprint $table) {
+            $table->dropColumn('postcode');
+        });
+    }
+};