account_id over online_id

[jonathan-rosa]

NP tickets has two fields relating to user: account_id (uint64_t that never changes) and online_id (string username)

The real LBP servers index users by account_id and account_id only, it only caches the result of online_id at login.

Indexing users by online_id makes the server thinks it's two different users and not the same user if the user renames their online ID or Sony forcefully renaming their online ID for whatever reason.