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.

pkg/fbs/scrabble.fbs

@@ -224,6 +224,12 @@ table Profile {
   // variant_preferences is the set of game variants the player allows themselves to be
   // matched into (engine.Variant labels), Erudit-first; the New Game picker is gated by it.
   variant_preferences:[string];
+  // email is the account's confirmed email address ("" when none); telegram_linked and
+  // vk_linked report whether a platform identity is attached. They drive the profile's
+  // link / unlink / change-email controls (all added trailing — backward-compatible).
+  email:string;
+  telegram_linked:bool;
+  vk_linked:bool;
 }
 
 // BlockStatus reports the caller's current manual block. The UI fetches it after any operation

pkg/fbs/scrabblefb/Profile.go

@@ -179,8 +179,40 @@ func (rcv *Profile) VariantPreferencesLength() int {
 	return 0
 }
 
+func (rcv *Profile) Email() []byte {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(30))
+	if o != 0 {
+		return rcv._tab.ByteVector(o + rcv._tab.Pos)
+	}
+	return nil
+}
+
+func (rcv *Profile) TelegramLinked() bool {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(32))
+	if o != 0 {
+		return rcv._tab.GetBool(o + rcv._tab.Pos)
+	}
+	return false
+}
+
+func (rcv *Profile) MutateTelegramLinked(n bool) bool {
+	return rcv._tab.MutateBoolSlot(32, n)
+}
+
+func (rcv *Profile) VkLinked() bool {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(34))
+	if o != 0 {
+		return rcv._tab.GetBool(o + rcv._tab.Pos)
+	}
+	return false
+}
+
+func (rcv *Profile) MutateVkLinked(n bool) bool {
+	return rcv._tab.MutateBoolSlot(34, n)
+}
+
 func ProfileStart(builder *flatbuffers.Builder) {
-	builder.StartObject(13)
+	builder.StartObject(16)
 }
 func ProfileAddUserId(builder *flatbuffers.Builder, userId flatbuffers.UOffsetT) {
 	builder.PrependUOffsetTSlot(0, flatbuffers.UOffsetT(userId), 0)
@@ -224,6 +256,15 @@ func ProfileAddVariantPreferences(builder *flatbuffers.Builder, variantPreferenc
 func ProfileStartVariantPreferencesVector(builder *flatbuffers.Builder, numElems int) flatbuffers.UOffsetT {
 	return builder.StartVector(4, numElems, 4)
 }
+func ProfileAddEmail(builder *flatbuffers.Builder, email flatbuffers.UOffsetT) {
+	builder.PrependUOffsetTSlot(13, flatbuffers.UOffsetT(email), 0)
+}
+func ProfileAddTelegramLinked(builder *flatbuffers.Builder, telegramLinked bool) {
+	builder.PrependBoolSlot(14, telegramLinked, false)
+}
+func ProfileAddVkLinked(builder *flatbuffers.Builder, vkLinked bool) {
+	builder.PrependBoolSlot(15, vkLinked, false)
+}
 func ProfileEnd(builder *flatbuffers.Builder) flatbuffers.UOffsetT {
 	return builder.EndObject()
 }