feat(profile): carry linked identities in the profile (email, telegram, vk)

Add email / telegram_linked / vk_linked to the Profile (fbs table + regenerated
Go/TS bindings, gateway ProfileResp + encodeProfile, backend DTO, UI model +
decode). They are filled outside the pure projection — Server.profileResponse now
reads the account's identities (like the banner seam) — and will drive the profile's
Add / Unlink / change-email controls.

ui/src/lib/codec.ts

@@ -354,6 +354,9 @@ export function decodeProfile(buf: Uint8Array): Profile {
     notificationsInAppOnly: p.notificationsInAppOnly(),
     variantPreferences: decodeVariantPreferences(p),
     banner: decodeBanner(p),
+    email: s(p.email()),
+    telegramLinked: p.telegramLinked(),
+    vkLinked: p.vkLinked(),
   };
 }