In the console feedback detail, show the sender's interface language (account
preferred_language) always, and — for a message that arrived through an external
connector (currently Telegram) — the bot they last used (en/ru, from the
account's service_language).
- style the About feedback button and the form's Send/attach/remove buttons with
the accent/border tokens used by the New Game CTA, so they follow light/dark
theme (the previous .btn/.ghost classes were not defined globally); the attach
button is a neutral 📎 icon button with an aria-label
- show a round badge on the About 'Feedback' button when a reply is waiting
- admin: one 'ban from feedback' checkbox shared by Delete and Delete-all (via
button formaction); hide Mark read when already read and Archive when archived
- e2e: match the About button by substring (its name gains the badge)