Function resolve_address_book 

pub fn resolve_address_book(
    input: &str,
    config: &Config,
) -> Result<ResolvedInput>

Resolves a user-supplied input string against the address book.

Supports @label shortcuts (e.g. @main-wallet) and direct address matching. Returns the original input unchanged if no match is found.

Errors

scope::error::ScopeError::InvalidInput when @label names no address book entry — a request fault, so handlers answer error_response(status_for(&e), ...) with 400.