Inside a Telegram/VK Mini App the host provider is auto-linked. Once the
player also linked an email, `canUnlink` turned true and the "Unlink"
control appeared on the host platform's own row — letting them unlink the
very platform they are signed in through, which is meaningless.
Gate the Telegram row on `!insideTelegram()` and the VK row on
`!insideVK()`, reusing the runtime host detectors that already gate the
"link" buttons. Symmetric: inside TG only the TG row is hidden (the VK row
still shows, since VK is not the current host), and vice versa. The web and
native builds are unchanged (both detectors are false there); the backend
is untouched — this is a UI display gate, and `linkUnlink` still refuses to
remove the last identity.
Docs: FUNCTIONAL.md (+_ru mirror).
Ilia Denisov