Confirm before launching an authentication flow for a model.
A provider-agnostic gate shown when a selected model needs credentials
that aren't detected, and starting the auth flow is disruptive enough
that the user should opt in first (e.g. an OAuth flow that launches a
browser and a multi-minute loopback wait). The caller supplies all copy
so the screen carries no provider assumptions; currently only the
openai_codex model-switcher path uses it.
Dismissal values:
True: proceed to the auth flow.False: go back without authenticating (also the outcome of Esc).Heading shown at the top of the dialog.
Explanatory copy. Pass a Content for inline styling, or a
plain string for unstyled text.
Key-hint line shown at the bottom.
Compose the confirmation dialog.
Apply ASCII border when needed.
Dismiss with True to proceed to the auth flow.
Dismiss with False to go back without authenticating.
The method name must stay cancel: the app owns a priority escape
binding that, for an active ModalScreen, dispatches to
action_cancel if present and otherwise falls through to
dismiss(None). Renaming this would silently regress Esc to a
None dismiss instead of an explicit "go back".