Fix: syncAgents() fails in cron context when connection is in non-root entity - #55

Testing

To reproduce:

1. Install plugin and configure the Wazuh connection in any non-root entity (entities_id != 0)
2. Trigger sync via cron or GLPI automatic actions
3. Observe that no agents are created despite a successful API/indexer connection

To verify the fix:

1. Apply the one-line change to syncAgents()
2. Also update the connection record's entities_id to match your target entity if it was left as 0
3. Trigger sync — agents should now appear with correct entities_id and is_deleted: 0

Root Cause

Session::getActiveEntity() returns 0 in any context without an active user session (cron, CLI). If the connection lives in entity 1+, the find() call returns nothing and sync silently does nothing.