Permission setup screen (2026-04-20)

Also maybe todo in hibi:

add permission setup screen (eg cal access location and notifications)

Scope

An onboarding / setup screen that requests the iOS permissions Hibi needs up-front:

Calendar access — EventKit read/write. Required to read existing events, write Hibi-created events, and (if Hibi owns calendar CRUD) manage calendars. See 2026-04-19-Notifications and calendar management.
Location — likely for location-aware event context (travel time, place-based reminders). Scope TBD; may be deferred past MVP.
Notifications — UNUserNotificationCenter authorization. Required if Hibi owns its own reminder UX rather than relying on Apple Calendar’s system notifications. See 2026-04-19-Notifications and calendar management — leaning toward Hibi owning it.

Onboarding UX needs a dedicated permission-request step rather than ad-hoc prompts at first use.
Order matters: ask for calendar before notifications, since notifications without calendar access is useless.
Handle denial gracefully — each permission should have a “why we need this” explanation and a path back to Settings.