chore: 上线前优化 — 清理调试日志/启用组件按需注入/补全组件声明

- 移除全项目 34 处调试 console.* 输出
- project.config.json: minified true、uploadWithSourceMap false、启用 lazyCodeLoading(requiredComponents 组件按需注入)
- pages/records/records.json 补全 ui-skeleton 组件声明(此前漏声明,WXML 已使用)
- 删除根目录残留 preview-buttons.html

app.js

@@ -118,7 +118,6 @@ App({
         }
         // else: no data anywhere — nothing to sync
       } catch (e) {
-        console.error('Cloud sync on launch failed:', e)
       }
     }
   },
@@ -145,7 +144,6 @@ App({
       const localChangedAt = wx.getStorageSync('_local_changed_at') || 0
       const keepLocal = cloudTs > 0 && localChangedAt > cloudTs
       if (keepLocal) {
-        console.log('[cloud] restore: keeping local single-value fields (local changed after cloud snapshot)')
       } else {
         if (cloudData.settings) {
           wx.setStorageSync('user_settings', cloudData.settings)
@@ -169,7 +167,6 @@ App({
       // records so it reflects actual history on this device.
       storage.recomputeStreak()
     } catch (e) {
-      console.error('Cloud restore failed:', e)
     }
   },