Remote command execution via action operations fails with "Host is monitored by proxy group, but its proxy assignment is still pending" when the operation targets a specific host or host group. The bug does not occur when the target is "Current host".

Steps to reproduce:

1. Create a proxy group with at least one active proxy
2. Create a host monitored by the proxy group
3. Link template or create a trapper item and trigger
4. Create a script: Alerts > Scripts > Create script
   • Scope: Action operation
   • Type: Script
   • Execute on: Zabbix agent
   • Command: echo test
5. Create a trigger action: Alerts > Actions > Trigger actions
   • Condition: trigger equals any trigger on the host
   • Operation: Run script (from step 4) on specific host (select the host from step 2)
6. Trigger the action (i.e. stop a monitored service, or use a trapper item)

Result:

Expected:
Executed command 

Workaround:
From

Change to

Result:

Issue:
The execute_commands() in src/zabbix_server/escalator/escalator.c gets proxy assignment from hosts table (where proxyid is always NULL when host is monitored by a proxy group) rather than from host_proxy table.

Manual script execution is also affected (src/libs/zbxtrapper/nodecommand.c).

"Current host" is handled by zbx_event_db_get_host() in src/libs/zbxevent/event_db.c and does it correctly.