fix: display group type names instead of IDs in automatic groups

[bwl21]

Problem

Automatic groups were displaying 'Unbekannter Typ' instead of actual group type names like 'Hauskreis', 'Mitarbeiterteam', etc.

Root Cause

• Group type ID was being accessed from wrong field path
• No mapping from group type IDs to human-readable names
• API response structure was not properly handled

Solution

• Fetch group types: Added API call to /group/grouptypes to create ID-to-name mapping
• Correct field access: Access groupTypeId from group.information.groupTypeId (not root level)
• Robust API handling: Handle both data array and direct array responses
• Interface updates: Added both groupTypeId (number) and groupTypeName (string) fields
• UI improvements: Display groupTypeName instead of groupTypeId in admin table

Technical Details

API Integration

• Fetch group types upfront and create Map for efficient lookups
• Include domainAttributes in groups API call for complete data
• Robust error handling with fallbacks

Field Access Priority

1. group.information.groupTypeId (correct path)
2. group.domainAttributes.groupTypeId (fallback)
3. group.groupTypeId (fallback)
4. 0 (default)

Files Changed

• src/composables/useAutomaticGroups.ts - Core logic for fetching and mapping group types
• src/components/automatic-groups/AutomaticGroupsAdmin.vue - UI updates for displaying group type names

Testing

• Group types are correctly fetched and mapped
• Automatic groups now display readable group type names
• Error handling works when group types API fails
• All lint checks pass
• No breaking changes to existing functionality

Documentation

• Complete session documentation created
• Lessons learned updated with ChurchTools API patterns
• Reusable pattern for other ID-to-name mappings

Resolves the grouptype display issue and provides a robust foundation for similar reference data mappings.