feat(price-reports): 运营后台「上报审核」页

用户上报"某平台比我们算的最低价更便宜"+截图,运营人工审核:
- price-reports/page.tsx: 列表+截图预览+通过(发1000金币)/拒绝(填理由),仿 withdraws
- layout.tsx: 侧边栏菜单加「上报审核」(FlagOutlined)
- lib/types.ts: PriceReport / PriceReportSummary DTO
- .gitignore: 加 CLAUDE.md(本地维护不入库,同 android/app-server 约定)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.gitignore

@@ -7,3 +7,6 @@ next-env.d.ts
 .DS_Store
 data/
 .run-logs/
+
+# CLAUDE.md 本地维护、不入库(同 android/app-server 约定)
+CLAUDE.md