Approve sets an allowance owned by the immediate caller. A direct user call updates the user's allowance. A realm cross-call updates the calling realm's allowance.
This differs from calling `Get(tokenKey).CallerTeller().Approve` within that realm, which updates the allowance of the realm's previous caller. To act as your own realm explicitly, use `Get(tokenKey).RealmTeller(0, cur)`.
Register records token under its rlmPath.symbol key and returns that key. Token.ID() carries a trailing sequence id (rlmPath.symbol.<id>) that keeps token identities/events unique, but the registry deliberately keys by rlmPath.symbol so lookups don't need to know the id, and so a realm cannot register two tokens under the same symbol (overwrite/alias guard).
Transfer moves tokens owned by the immediate caller. A direct user call spends the user's balance. A realm cross-call spends the calling realm's balance.
This differs from calling `Get(tokenKey).CallerTeller().Transfer` within that realm, which spends the balance of the realm's previous caller. To act as your own realm explicitly, use `Get(tokenKey).RealmTeller(0, cur)`.
TransferFrom spends an allowance as the immediate caller. A direct user call uses the user as the spender. A realm cross-call uses the calling realm as the spender.
This differs from calling `Get(tokenKey).CallerTeller().TransferFrom` within that realm, which uses the realm's previous caller as the spender. To act as your own realm explicitly, use `Get(tokenKey).RealmTeller(0, cur)`.
