Add player auth migrate account API

[tudddorrr]

No description provided.

[claude]

PR Review: Add player auth migrate account API

Overall structure is clean and follows existing patterns well.

---

Potential Bugs or Issues

Session state is cleared but never restored after migration

In SessionManager.HandleAccountMigrated, ClearSession(false) deletes TaloSessionToken from PlayerPrefs, but the migration response only returns an alias — no sessionToken or socketToken. As a result:

1. On the next app launch, CheckForSession() returns false → OnSessionNotFound fires → the player must log in again even though migration succeeded.
2. TaloSessionIdentifier in PlayerPrefs is never updated or cleared — it retains the old identifier, leaving stale data.
3. InvokeIdentifiedEvent() fires immediately after (signalling the player is identified), but the identified state is not persisted.

Contrast with HandleSessionCreated, which saves both sessionToken and updates TaloSessionIdentifier via SaveSession().

If the intent is that the existing session remains valid after migration (just with a new alias), then ClearSession should not be called — only SetNewAlias + SetIdentifierPlayerPref are needed, matching the pattern in HandleIdentifierUpdated.

If the intent is to require a fresh login after migration, then InvokeIdentifiedEvent() should not be called, and CurrentAlias should not be set.

If the backend does invalidate the old session on migration, the response should include a sessionToken (and socketToken) so the new session can be persisted.

---

Code Quality, Performance, Security, Backwards Compatibility

No issues found.