ClientState: consider replacing confirm_frozen and expired methods with a "status" instead

[Farhad-Shabani]

Problem Statement

Context: #531 (comment)

Currently, the ClientState trait exposes three interfaces: is_frozen, expired, and frozen_height for checking the client status. However, these methods appear to make some underlying assumptions about the characteristics of the host chain.
Further investigation is required to ensure their compatibility with any chains. To address this issue, it is suggested that we adopt the approach taken by IBC-go, which provides a more practical and robust status() API.