整理：合并零散迁移文件，36个简化为24个纯建表迁移

- users 表：吸收 s_color类型变更/sign/question/answer/vip_level_id/has_received_new_gift
- rooms 表：吸收 visit_num、announcement
- sysparam 表：吸收全部 seed（99级经验/权限等级/钓鱼/魅力/排行榜，直接写最终值）
- 新增 create_shop_tables（shop_items+user_purchases+username_blacklist+默认商品）
- 新增 create_user_currency_logs_table（积分流水表含完整索引）
- 删除 14 个已吸收的 add_column / seed 零散迁移

database/migrations/2026_02_26_040521_create_messages_table.php

@@ -0,0 +1,35 @@
+<?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('messages', function (Blueprint $table) {
+            $table->id();
+            $table->integer('room_id')->index()->comment('房间ID');
+            $table->string('from_user', 50)->index()->comment('发送者');
+            $table->string('to_user', 50)->nullable()->index()->comment('接收者');
+            $table->text('content')->comment('消息内容');
+            $table->tinyInteger('is_secret')->default(0)->comment('是否私聊');
+            $table->string('font_color', 50)->nullable()->comment('字体颜色');
+            $table->string('action', 50)->nullable()->comment('动作');
+            $table->dateTime('sent_at')->useCurrent()->index()->comment('发送时间');
+            $table->timestamps();
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::dropIfExists('messages');
+    }
+};