feat: 管理后台改造 + 小程序最新章节逻辑 + 变更文档

【soul-admin 管理后台】
- 交易中心 → 推广中心（侧边栏与页面标题）
- 移除 5 个冗余按钮，仅保留「API 接口」
- 删除按钮改为悬停显示
- 免费/付费可点击切换（单击切换，双击付费可设金额）
- 加号移至章节右侧（序言、附录等），小节内移除加号
- 章节与小节支持拖拽排序
- 持续隐藏「上传内容」等按钮，解决双页面问题

【小程序首页 - 最新章节】
- latest-chapters API: 2 日内有新章取最新 3 章，否则随机免费章
- 首页 Banner 调用 /api/book/latest-chapters
- 标签动态显示「最新更新」或「为你推荐」

【开发文档】
- 新增 soul-admin变更记录_v2026-02.md

Co-authored-by: Cursor <cursoragent@cursor.com>

app/api/book/latest-chapters/route.ts

@@ -1,55 +1,96 @@
 // app/api/book/latest-chapters/route.ts
-// 获取最新章节列表
+// 获取最新章节：有2日内更新则取最新3章，否则随机取免费章节
 
-import { NextRequest, NextResponse } from 'next/server'
-import { getBookStructure } from '@/lib/book-file-system'
+import { NextResponse } from 'next/server'
+import { query } from '@/lib/db'
 
-export async function GET(req: NextRequest) {
+const TWO_DAYS_MS = 2 * 24 * 60 * 60 * 1000
+
+export async function GET() {
   try {
-    const bookStructure = getBookStructure()
-    
-    // 获取所有章节并按时间排序
-    const allChapters: any[] = []
-    
-    bookStructure.forEach((part: any) => {
-      part.chapters.forEach((chapter: any) => {
-        allChapters.push({
-          id: chapter.slug,
-          title: chapter.title,
-          part: part.title,
-          words: Math.floor(Math.random() * 3000) + 1500, // 模拟字数
-          updateTime: getRelativeTime(new Date(Date.now() - Math.random() * 30 * 24 * 60 * 60 * 1000)),
-          readTime: Math.ceil((Math.random() * 3000 + 1500) / 300)
-        })
+    let allChapters: Array<{
+      id: string
+      title: string
+      part: string
+      isFree: boolean
+      price: number
+      updatedAt: Date | string | null
+      createdAt: Date | string | null
+    }> = []
+
+    try {
+      const dbRows = (await query(`
+        SELECT id, part_title, section_title, is_free, price, created_at, updated_at
+        FROM chapters
+        ORDER BY sort_order ASC, id ASC
+      `)) as any[]
+
+      if (dbRows?.length > 0) {
+        allChapters = dbRows.map((row: any) => ({
+          id: row.id,
+          title: row.section_title || row.title || '',
+          part: row.part_title || '真实的行业',
+          isFree: !!row.is_free,
+          price: row.price || 0,
+          updatedAt: row.updated_at || row.created_at,
+          createdAt: row.created_at
+        }))
+      }
+    } catch (e) {
+      console.log('[latest-chapters] 数据库读取失败:', (e as Error).message)
+    }
+
+    if (allChapters.length === 0) {
+      return NextResponse.json({
+        success: true,
+        banner: { id: '1.1', title: '荷包：电动车出租的被动收入模式', part: '真实的人' },
+        label: '为你推荐',
+        chapters: [],
+        hasNewUpdates: false
       })
+    }
+
+    const now = Date.now()
+    const sorted = [...allChapters].sort((a, b) => {
+      const ta = a.updatedAt ? new Date(a.updatedAt).getTime() : 0
+      const tb = b.updatedAt ? new Date(b.updatedAt).getTime() : 0
+      return tb - ta
     })
 
-    // 取最新的3章
-    const latestChapters = allChapters.slice(0, 3)
+    const mostRecentTime = sorted[0]?.updatedAt ? new Date(sorted[0].updatedAt).getTime() : 0
+    const hasNewUpdates = now - mostRecentTime < TWO_DAYS_MS
+
+    let banner: { id: string; title: string; part: string }
+    let label: string
+    let chapters: typeof allChapters
+
+    if (hasNewUpdates && sorted.length > 0) {
+      chapters = sorted.slice(0, 3)
+      banner = { id: chapters[0].id, title: chapters[0].title, part: chapters[0].part }
+      label = '最新更新'
+    } else {
+      const freeChapters = allChapters.filter((c) => c.isFree || c.price === 0)
+      const candidates = freeChapters.length > 0 ? freeChapters : allChapters
+      const shuffled = [...candidates].sort(() => Math.random() - 0.5)
+      chapters = shuffled.slice(0, 3)
+      banner = chapters[0]
+        ? { id: chapters[0].id, title: chapters[0].title, part: chapters[0].part }
+        : { id: allChapters[0].id, title: allChapters[0].title, part: allChapters[0].part }
+      label = '为你推荐'
+    }
 
     return NextResponse.json({
       success: true,
-      chapters: latestChapters,
-      total: allChapters.length
+      banner,
+      label,
+      chapters: chapters.map((c) => ({ id: c.id, title: c.title, part: c.part, isFree: c.isFree })),
+      hasNewUpdates
     })
   } catch (error) {
-    console.error('获取章节失败:', error)
+    console.error('[latest-chapters] Error:', error)
     return NextResponse.json(
-      { error: '获取章节失败' },
+      { success: false, error: '获取失败' },
       { status: 500 }
     )
   }
 }
-
-// 获取相对时间
-function getRelativeTime(date: Date): string {
-  const now = new Date()
-  const diff = now.getTime() - date.getTime()
-  const days = Math.floor(diff / (1000 * 60 * 60 * 24))
-  
-  if (days === 0) return '今天'
-  if (days === 1) return '昨天'
-  if (days < 7) return `${days}天前`
-  if (days < 30) return `${Math.floor(days / 7)}周前`
-  return `${Math.floor(days / 30)}个月前`
-}