[FEAT] 優化帳號管理授權顯示邏輯與 UI 樣式一致性

database/migrations/2026_03_23_093421_create_machine_user_table.php

@@ -0,0 +1,31 @@
+<?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::create('machine_user', function (Blueprint $table) {
+            $table->id();
+            $table->foreignId('machine_id')->constrained()->onDelete('cascade');
+            $table->foreignId('user_id')->constrained()->onDelete('cascade');
+            $table->timestamps();
+
+            $table->unique(['machine_id', 'user_id']); // Ensure uniqueness
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::dropIfExists('machine_user');
+    }
+};