v0.5.3: local speed-dial accounts (family without Telegram)

Added

• Local speed-dial accounts, for family without Telegram: a local account is a household name with no
  Telegram behind it, whose entire surface is its no-login /r/ remote-control link. It is never
  vouched, can't be claimed by any Telegram sender (even one with the same @username), and is
  permanently speed-dial-only. Because the link is the account, a local's share link can be minted
  never-expiring (Telegram guest links still always expire). The Access tab gains a Telegram/Local
  selector, local rows show a house badge with link-first copy, and the printable sheet gives
  open-your-link instructions. Name collisions with existing pads, vouches, and the allowlist are
  refused both ways.