Option to periodically clear the public.activity_log_event database table

**Is your feature request related to a problem? Please describe.**
The database could grow very large over time if there is no retention for the tables.

**Describe the solution you'd like**
An option to periodically clear the entries based on timestamps (e.g., "Delete all logs older than x days").

**Describe alternatives you've considered**
Create my own script to be triggered by cron to handle this task.

**Additional context**
Low priority, but it would be nice to have this feature implemented directly in Defguard.

Result:
- Have entries in the activity log table in the dev environment older than a week.
- Set the cleanup frequency to 7d
- Show that entries older than 7d were removed.