Module capabilities 

/capabilities client. Shape from architecture.md §6.

Structs

ArtifactSupport

BackendFamily

CapabilitiesResponse

FeatureSupport

ProfileSupport

TakeoverSupport

Human-takeover panel support. provider names the concrete screen-share method (kasmvnc, …) — open-ended like BackendFamily.family, so adding a provider does not change this shape.