diff --git a/backend/migrations/000001_init.sql b/backend/migrations/000001_init.sql
index df951a4..df6009a 100644
--- a/backend/migrations/000001_init.sql
+++ b/backend/migrations/000001_init.sql
@@ -1,3 +1,15 @@
+-- ============================================
+-- 数据库初始化脚本
+-- 包含所有表结构定义
+-- ============================================
+
+SET NAMES utf8mb4;
+SET FOREIGN_KEY_CHECKS = 0;
+
+-- -------------------------------------------
+-- 用户相关表
+-- -------------------------------------------
+
 CREATE TABLE users (
   id BIGINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
   phone VARCHAR(32) NOT NULL,
@@ -29,6 +41,10 @@ CREATE TABLE user_realname (
   KEY idx_user_realname_provider_order_no (provider_order_no)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
 
+-- -------------------------------------------
+-- 游戏账号和商品表
+-- -------------------------------------------
+
 CREATE TABLE game_accounts (
   id BIGINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
   owner_id BIGINT UNSIGNED NOT NULL,
@@ -67,6 +83,10 @@ CREATE TABLE rental_listings (
   KEY idx_rental_listings_filter (status, review_status, in_transaction, price)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
 
+-- -------------------------------------------
+-- 订单相关表
+-- -------------------------------------------
+
 CREATE TABLE rental_orders (
   id BIGINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
   order_no VARCHAR(64) NOT NULL,
@@ -136,6 +156,10 @@ CREATE TABLE handoff_records (
   KEY idx_handoff_records_order_id (order_id)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
 
+-- -------------------------------------------
+-- 钱包相关表
+-- -------------------------------------------
+
 CREATE TABLE wallet_accounts (
   id BIGINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
   user_id BIGINT UNSIGNED NOT NULL,
@@ -166,6 +190,10 @@ CREATE TABLE wallet_ledger (
   KEY idx_wallet_ledger_biz (biz_type, biz_no)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
 
+-- -------------------------------------------
+-- 纠纷和通知表
+-- -------------------------------------------
+
 CREATE TABLE disputes (
   id BIGINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
   order_id BIGINT UNSIGNED NOT NULL,
@@ -213,6 +241,10 @@ CREATE TABLE audit_logs (
   KEY idx_audit_logs_biz (biz_type, biz_id)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
 
+-- -------------------------------------------
+-- 管理员和权限表
+-- -------------------------------------------
+
 CREATE TABLE admin_users (
   id BIGINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
   username VARCHAR(64) NOT NULL,
@@ -262,6 +294,10 @@ CREATE TABLE role_permissions (
   UNIQUE KEY uk_role_permissions_role_permission (role_id, permission_id)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
 
+-- -------------------------------------------
+-- 系统配置表
+-- -------------------------------------------
+
 CREATE TABLE system_configs (
   id BIGINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
   `key` VARCHAR(128) NOT NULL,
@@ -272,3 +308,65 @@ CREATE TABLE system_configs (
   updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
   UNIQUE KEY uk_system_configs_key (`key`)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
+
+-- -------------------------------------------
+-- 客服聊天表
+-- -------------------------------------------
+
+CREATE TABLE chat_conversations (
+  id BIGINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
+  order_id BIGINT UNSIGNED NOT NULL,
+  type VARCHAR(32) NOT NULL DEFAULT 'order_group',
+  title VARCHAR(128) NOT NULL,
+  status VARCHAR(32) NOT NULL DEFAULT 'active',
+  last_message_id BIGINT UNSIGNED NULL,
+  last_message_preview VARCHAR(255) NOT NULL DEFAULT '',
+  last_message_at DATETIME NULL,
+  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+  UNIQUE KEY uk_chat_conversations_order_id (order_id),
+  KEY idx_chat_conversations_last_message_at (last_message_at)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
+
+CREATE TABLE chat_participants (
+  id BIGINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
+  conversation_id BIGINT UNSIGNED NOT NULL,
+  participant_type VARCHAR(16) NOT NULL,
+  participant_id BIGINT UNSIGNED NOT NULL,
+  role VARCHAR(32) NOT NULL,
+  remark VARCHAR(128) NOT NULL DEFAULT '',
+  last_read_at DATETIME NULL,
+  joined_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+  UNIQUE KEY uk_chat_participants_member (conversation_id, participant_type, participant_id),
+  KEY idx_chat_participants_participant (participant_type, participant_id),
+  KEY idx_chat_participants_conversation (conversation_id)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
+
+CREATE TABLE chat_messages (
+  id BIGINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
+  conversation_id BIGINT UNSIGNED NOT NULL,
+  sender_type VARCHAR(16) NOT NULL,
+  sender_id BIGINT UNSIGNED NOT NULL DEFAULT 0,
+  sender_role VARCHAR(32) NOT NULL DEFAULT '',
+  content_type VARCHAR(32) NOT NULL DEFAULT 'text',
+  content TEXT NULL,
+  attachment_urls JSON NULL,
+  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  KEY idx_chat_messages_conversation_id (conversation_id, id),
+  KEY idx_chat_messages_created_at (created_at)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
+
+CREATE TABLE chat_quick_replies (
+  id BIGINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
+  admin_user_id BIGINT UNSIGNED NOT NULL DEFAULT 0 COMMENT '0=全局, >0=个人',
+  title VARCHAR(64) NOT NULL COMMENT '快捷回复标题',
+  content TEXT NOT NULL COMMENT '回复内容',
+  sort_order INT NOT NULL DEFAULT 0 COMMENT '排序',
+  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+  INDEX idx_admin_user_id (admin_user_id)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci COMMENT='快捷回复模板';
+
+SET FOREIGN_KEY_CHECKS = 1;
diff --git a/backend/migrations/000002_chat.sql b/backend/migrations/000002_chat.sql
deleted file mode 100644
index 12e7f1a..0000000
--- a/backend/migrations/000002_chat.sql
+++ /dev/null
@@ -1,47 +0,0 @@
-CREATE TABLE IF NOT EXISTS chat_conversations (
-  id BIGINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
-  order_id BIGINT UNSIGNED NOT NULL,
-  type VARCHAR(32) NOT NULL DEFAULT 'order_group',
-  title VARCHAR(128) NOT NULL,
-  status VARCHAR(32) NOT NULL DEFAULT 'active',
-  last_message_id BIGINT UNSIGNED NULL,
-  last_message_preview VARCHAR(255) NOT NULL DEFAULT '',
-  last_message_at DATETIME NULL,
-  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
-  updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
-  UNIQUE KEY uk_chat_conversations_order_id (order_id),
-  KEY idx_chat_conversations_last_message_at (last_message_at)
-) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
-
-CREATE TABLE IF NOT EXISTS chat_participants (
-  id BIGINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
-  conversation_id BIGINT UNSIGNED NOT NULL,
-  participant_type VARCHAR(16) NOT NULL,
-  participant_id BIGINT UNSIGNED NOT NULL,
-  role VARCHAR(32) NOT NULL,
-  last_read_at DATETIME NULL,
-  joined_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
-  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
-  updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
-  UNIQUE KEY uk_chat_participants_member (conversation_id, participant_type, participant_id),
-  KEY idx_chat_participants_participant (participant_type, participant_id),
-  KEY idx_chat_participants_conversation (conversation_id)
-) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
-
-CREATE TABLE IF NOT EXISTS chat_messages (
-  id BIGINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
-  conversation_id BIGINT UNSIGNED NOT NULL,
-  sender_type VARCHAR(16) NOT NULL,
-  sender_id BIGINT UNSIGNED NOT NULL DEFAULT 0,
-  sender_role VARCHAR(32) NOT NULL DEFAULT '',
-  content_type VARCHAR(32) NOT NULL DEFAULT 'text',
-  content TEXT NULL,
-  attachment_urls JSON NULL,
-  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
-  KEY idx_chat_messages_conversation_id (conversation_id, id),
-  KEY idx_chat_messages_created_at (created_at)
-) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
-
-INSERT INTO system_configs (`key`, `value`, description)
-VALUES ('chat.default_support_admin_id', '1', '订单群聊默认接入的客服管理员 ID')
-ON DUPLICATE KEY UPDATE description = VALUES(description);
diff --git a/backend/migrations/000002_rbac_seed.sql b/backend/migrations/000002_seed.sql
similarity index 68%
rename from backend/migrations/000002_rbac_seed.sql
rename to backend/migrations/000002_seed.sql
index 22b4bbf..ecc9d0a 100644
--- a/backend/migrations/000002_rbac_seed.sql
+++ b/backend/migrations/000002_seed.sql
@@ -1,7 +1,14 @@
--- RBAC seed: 默认角色和权限
+-- ============================================
+-- 初始数据脚本
+-- 包含权限、角色、系统配置等基础数据
+-- ============================================
+
 SET NAMES utf8mb4;
 
--- 插入权限
+-- -------------------------------------------
+-- 权限数据
+-- -------------------------------------------
+
 INSERT INTO permissions (code, name, resource, action) VALUES
 ('dashboard:view',        '查看仪表盘',       'dashboard',      'view'),
 ('user:view',             '查看用户',         'user',           'view'),
@@ -26,7 +33,10 @@ INSERT INTO permissions (code, name, resource, action) VALUES
 ('audit_log:view',        '查看审计日志',     'audit_log',      'view')
 ON DUPLICATE KEY UPDATE name = VALUES(name);
 
--- 插入角色
+-- -------------------------------------------
+-- 角色数据
+-- -------------------------------------------
+
 INSERT INTO roles (code, name, description) VALUES
 ('super_admin', '超级管理员', '拥有所有权限，不可被删除'),
 ('cs',          '客服',       '处理用户咨询、群聊、纠纷仲裁'),
@@ -34,6 +44,10 @@ INSERT INTO roles (code, name, description) VALUES
 ('finance',     '财务',       '查看资金流水、订单信息')
 ON DUPLICATE KEY UPDATE name = VALUES(name), description = VALUES(description);
 
+-- -------------------------------------------
+-- 角色权限关联
+-- -------------------------------------------
+
 -- super_admin 拥有所有权限
 INSERT IGNORE INTO role_permissions (role_id, permission_id)
 SELECT r.id, p.id FROM roles r CROSS JOIN permissions p WHERE r.code = 'super_admin';
@@ -53,6 +67,19 @@ INSERT IGNORE INTO role_permissions (role_id, permission_id)
 SELECT r.id, p.id FROM roles r, permissions p
 WHERE r.code = 'finance' AND p.code IN ('dashboard:view', 'wallet:view', 'order:view');
 
--- 默认 admin 用户自动绑定 super_admin 角色
-INSERT IGNORE INTO admin_user_roles (admin_user_id, role_id)
-SELECT au.id, r.id FROM admin_users au, roles r WHERE au.username = 'admin' AND r.code = 'super_admin';
+-- -------------------------------------------
+-- 系统配置
+-- -------------------------------------------
+
+INSERT INTO system_configs (`key`, `value`, description) VALUES
+('order.handoff_timeout_minutes', '60', '交接超时时间（分钟）'),
+('order.return_timeout_minutes', '1440', '归还超时时间（分钟）'),
+('sms.rate_limit_per_minute', '1', '短信限流：每分钟最多发送次数'),
+('sms.rate_limit_per_hour', '5', '短信限流：每小时最多发送次数'),
+('wallet.min_deposit', '50', '最低押金金额'),
+('platform.fee_ratio', '0.1', '平台抽成比例'),
+('listing.review_required', 'true', '商品是否需要审核'),
+('order.pending_payment_timeout_minutes', '15', '待支付超时时间（分钟）'),
+('chat.default_support_admin_id', '1', '订单群聊默认接入的客服管理员 ID'),
+('chat.auto_welcome_message', '欢迎加入订单群聊！如有任何问题，请随时沟通。', '建群后自动发送的欢迎话术')
+ON DUPLICATE KEY UPDATE description = VALUES(description);
diff --git a/backend/migrations/000007_chat_enhancements.sql b/backend/migrations/000007_chat_enhancements.sql
deleted file mode 100644
index 466a571..0000000
--- a/backend/migrations/000007_chat_enhancements.sql
+++ /dev/null
@@ -1,19 +0,0 @@
--- 会话备注字段（个人级别）
-ALTER TABLE chat_participants ADD COLUMN remark VARCHAR(128) DEFAULT '' AFTER last_read_at;
-
--- 快捷回复表
-CREATE TABLE IF NOT EXISTS chat_quick_replies (
-    id BIGINT PRIMARY KEY AUTO_INCREMENT,
-    admin_user_id BIGINT NOT NULL DEFAULT 0 COMMENT '0=全局, >0=个人',
-    title VARCHAR(64) NOT NULL COMMENT '快捷回复标题',
-    content TEXT NOT NULL COMMENT '回复内容',
-    sort_order INT NOT NULL DEFAULT 0 COMMENT '排序',
-    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
-    updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
-    INDEX idx_admin_user_id (admin_user_id)
-) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='快捷回复模板';
-
--- 建群自动话术配置
-INSERT INTO system_configs (`key`, `value`, description) VALUES
-('chat.auto_welcome_message', '欢迎加入订单群聊！如有任何问题，请随时沟通。', '建群后自动发送的欢迎话术')
-ON DUPLICATE KEY UPDATE description = VALUES(description);
diff --git a/scripts/dev.sh b/scripts/dev.sh
index dcd879c..099dc35 100755
--- a/scripts/dev.sh
+++ b/scripts/dev.sh
@@ -70,41 +70,14 @@ init_database() {
   )"
 
   if [[ "${table_count}" == "0" ]]; then
-    log "首次启动，初始化数据库结构..."
+    log "首次启动，初始化数据库..."
     local migration
     for migration in "${ROOT_DIR}"/backend/migrations/*.sql; do
       log "执行迁移：$(basename "${migration}")"
       docker exec -i hfb-mysql mysql -uhfb -psecret --default-character-set=utf8mb4 hfb_sys < "${migration}"
     done
   else
-    local chat_table_count
-    chat_table_count="$(
-      docker exec hfb-mysql mysql -uhfb -psecret -N -s -e \
-        "SELECT COUNT(*) FROM information_schema.tables WHERE table_schema = 'hfb_sys' AND table_name = 'chat_conversations';" 2>/dev/null
-    )" || chat_table_count="0"
-    if [[ "${chat_table_count}" == "0" ]]; then
-      log "补充聊天表迁移：000002_chat.sql"
-      docker exec -i hfb-mysql mysql -uhfb -psecret --default-character-set=utf8mb4 hfb_sys < "${ROOT_DIR}/backend/migrations/000002_chat.sql"
-    fi
-
-    local role_count
-    role_count="$(
-      docker exec hfb-mysql mysql -uhfb -psecret -N -s -e \
-        "SELECT COUNT(*) FROM information_schema.tables WHERE table_schema = 'hfb_sys' AND table_name = 'roles';" 2>/dev/null
-    )" || role_count="0"
-    if [[ "${role_count}" != "0" ]]; then
-      local seed_count
-      seed_count="$(
-        docker exec hfb-mysql mysql -uhfb -psecret -N -s -e \
-          "SELECT COUNT(*) FROM roles;" 2>/dev/null
-      )" || seed_count="0"
-      if [[ "${seed_count}" == "0" ]]; then
-        log "补充 RBAC 种子数据：000002_rbac_seed.sql"
-        docker exec -i hfb-mysql mysql -uhfb -psecret --default-character-set=utf8mb4 hfb_sys < "${ROOT_DIR}/backend/migrations/000002_rbac_seed.sql" || true
-      fi
-    fi
-
-    log "数据库迁移检查完成"
+    log "数据库已存在，跳过迁移（使用 DEV_RESET_DB=1 重建）"
   fi
 }