Add Event.created_by (the owner, used later by the access service to let an
event's creator edit it).
Validate that an event's season/location/opponent — and an EventSeries'
location/opponent — belong to the event's club. The teams M2M cannot be checked
in clean() (M2M rows are written after save), so an m2m_changed pre_add receiver
rejects teams from another club.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Bernard Siebens
22d971d48c