EventFirmwareCard

Card announcing that the connected device is running an event firmware edition, and the entry point to EventInfoSheet for that event's welcome message, venue, dates, and links.

This is where event branding lives: the app bar keeps the Meshtastic logo, so the edition is reported alongside the other facts about the connected device rather than replacing the app's own identity.

The caller is responsible for hiding this once the event has ended (hasEnded); a finished event gets the "return to standard firmware" card instead.