Variable attributeClaimChoices

attributeClaimChoices: () => { attribute: string; from: string[] }[] = ...

- (): { attribute: string; from: string[] }[]
- The attributes an attribute claim can name that the catalogue cannot: what this realm's attribute sources and inbound federation mappings write, each with who writes it.
  
  Returns { attribute: string; from: string[] }[]
  [{ attribute, from: [..] }], sorted by attribute