- CODE_GUIDELINES: add vereinfacht/ to project structure, required-fields note, link to vereinfacht-api
- docs/vereinfacht-api.md: filter API, minimal create payload, no extra required fields
- feature-roadmap: member-contact sync implemented, link to doc
- Member field settings: required only from email + settings (no API override)
- Member resource validation: required fields from settings only
- Gettext: remove obsolete 'Required for Vereinfacht integration' string
- find_contact_by_email uses GET with filter[isExternal]=true and filter[email]
- vereinfacht_required_member_fields is now empty (API accepts minimal payload)