feat: 完成独立的邀请与达人榜系统架构

database/migrations/2026_03_12_092039_add_inviter_id_to_users_table.php

@@ -0,0 +1,30 @@
+<?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->unsignedBigInteger('inviter_id')->nullable()->after('id')->comment('邀请人ID');
+            $table->foreign('inviter_id')->references('id')->on('users')->nullOnDelete();
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::table('users', function (Blueprint $table) {
+            $table->dropForeign(['inviter_id']);
+            $table->dropColumn('inviter_id');
+        });
+    }
+};