Zabbix

.......P.. [ZBX-25024] changed Zabbix proxy to use history write time rather than value timestamp when discarding old values

Merge in ZBX/zabbix from feature/ZBX-25024-7.1 to master

* commit '6acc52cc5b2516368d762e45857cda7777531447':
  .......P.. [ZBX-25024] fixed proxy skipping value between batches when fetching data for sending from memory buffer
  .......... [ZBX-25024] fixed proxy_history table index numbering in schema
  .......... [ZBX-25024] removed redundant database patch
  .D........ [ZBX-25024] added changelog entry
  .......P.. [ZBX-25024] changed proxy memory buffer to use write_clock when checking for expired records
  .......P.. [ZBX-25024] changed housekeeper to use write_clock when removing too old records from proxy_history table
  .......P.. [ZBX-25024] added optional database patch to add proxy_history index on proxy