fix: admin records filter by user_id instead of keyword search

- RecordView passes user_id as separate filter param, not as keyword
- Admin records endpoint forwards user_id to DAO
- treatmentDao.listAdmin supports exact user_id match filter
- Added visible filter tag with clear button in RecordView

server/src/routes/admin.js

@@ -227,6 +227,7 @@ router.get('/records', requireAdmin, wrap(async (req, res) => {
   const { page, pageSize, offset } = pageParams(req.query)
   const { records, total } = await treatmentDao.listAdmin({
     keyword: req.query.keyword,
+    userId: req.query.user_id,
     dateFrom: req.query.date_from,
     dateTo: req.query.date_to,
     pageSize,