Draft: ADR Private individual proofs possession of their devices using eID

Relates to planning#2 and planning#186 (eID verification ticket)

See also planning#190

based on

and https://gitlab.opencode.de/it-planungsrat/fit-ab/zapuk/-/blob/main/Zielarchitektur/Architekturentscheidungen/ADR-0014-Authentizit%C3%A4t-Identit%C3%A4t-von-Privatpersonen.md?ref_type=heads#option-2-identifikation-mittels-zentralem-b%C3%BCrgerkonto-gem%C3%A4%C3%9F--3-ozg-bundid

Part of https://gitlab.opencode.de/fitko/matrix-g2x/planning/-/issues/?sort=created_date&state=opened&search=Eid&first_page_size=20&show=eyJpaWQiOiIzNiIsImZ1bGxfcGF0aCI6ImZpdGtvL21hdHJpeC1nMngvcGxhbm5pbmciLCJpZCI6MzEwNDJ9

Signed-off-by: Kim Brose kim.brose@nordeck.net