Currently, the Host and Host group conditions in Complex Event Processing (CEP) do not provide any lookup or autocomplete when using the Contains or Does not contain operators.

While these operators are intended for substring matching rather than exact object selection, users still have to manually type host or host group names. This becomes inconvenient in larger environments where host and host group names are long or numerous.

It would improve usability if these fields provided autocomplete suggestions based on existing host and host group names while still allowing free-text input.

The matching semantics should remain unchanged:

• Equals / Does not equal → exact match
• Contains / Does not contain → substring match

Only the input experience would be improved by suggesting existing names as the user types.

Benefits

• Easier configuration in large environments.
• Reduces typing mistakes.
• No change to CEP matching behaviour or API.
• Consistent with other Zabbix object selection fields where autocomplete is already available.