pattern_text achieves better compression if the index is sorted by the template_id of the largest pattern_text field. Sorting can be done manually with the index.sort.* settings, but if possible we should sort automatically.

Specifically, we should do the following:

• if an index contains a field called message of type pattern_text:
  • if mode=logsdb and there is a host.name field: sort by host.name, message.template_id, timestamp
  • else sort by message.template_id, timestamp

Depends on #129062