fix: fetch token balance after wallet registration

[pedroferreira1]

Motivation

After a token swap or a nano contract transaction in Reown that has a new token registration, the balance was not being fetched.

Acceptance Criteria

• Create a util method for token registration and metadata fetch
• Use these util methods in all places where we register tokens

Note: in the token creation register wouldn't be necessary to fetch the balance neither the metadata but I decided to handle all places the same for consistency.

Security Checklist

• Make sure you do not include new dependencies in the project unless strictly necessary and do not include dev-dependencies as production ones. More dependencies increase the possibility of one of them being hijacked and affecting us.