feat: 系统配置 + 用户签名

- 新增 sys_config 表，存储应用版本号、标语、描述
- 关于小菜弹窗版本号改为从数据库动态获取
- 用户表新增 slogan 字段（个性签名）
- 编辑资料页面支持修改签名
- 管理后台新增系统配置管理页面
- 更新 CLAUDE.md 文档

client/src/stores/user.ts

@@ -10,6 +10,10 @@ export const useUserStore = defineStore('user', () => {
     return userInfo.value?.nickname || uni.getStorageSync('xc:nickname') || '小菜'
   })
 
+  const slogan = computed(() => {
+    return userInfo.value?.slogan || '记账小能手'
+  })
+
   const avatarUrl = computed(() => {
     const filename = userInfo.value?.avatar_url || uni.getStorageSync('xc:avatar_url') || ''
     if (!filename) return ''
@@ -28,10 +32,17 @@ export const useUserStore = defineStore('user', () => {
     }
   }
 
-  async function updateProfile(nickname: string) {
-    await api.updateNickname(nickname)
-    if (userInfo.value) userInfo.value.nickname = nickname
-    uni.setStorageSync('xc:nickname', nickname)
+  async function updateProfile(data: { nickname?: string; slogan?: string }) {
+    const nickname = data.nickname ?? userInfo.value?.nickname ?? ''
+    const slogan = data.slogan ?? userInfo.value?.slogan ?? ''
+    await api.updateNickname(nickname, slogan)
+    if (userInfo.value) {
+      if (data.nickname !== undefined) userInfo.value.nickname = data.nickname
+      if (data.slogan !== undefined) userInfo.value.slogan = data.slogan
+    }
+    if (data.nickname !== undefined) {
+      uni.setStorageSync('xc:nickname', data.nickname)
+    }
   }
 
   async function uploadAvatar(filePath: string) {
@@ -41,5 +52,5 @@ export const useUserStore = defineStore('user', () => {
     return avatarUrl.value
   }
 
-  return { userInfo, nickname, avatarUrl, fetchUserInfo, updateProfile, uploadAvatar }
+  return { userInfo, nickname, slogan, avatarUrl, fetchUserInfo, updateProfile, uploadAvatar }
 })