feat: Update Claim Asset Flow

[fcavazzoli]

Use CAP to store ClaimableMessages

We are doing this to avoid having to call remove_claimable after the user withdraws the asset on ETH side.
Since CAP is scalable, remove_messages is no longer necessary.

• remove_claimable candid method is going to be deleted.
• get_claimable_messages candid method is going to be deleted because that query is being handled by CAP root.

Next

• after perform some test. If everything works, delete the entire folder aws/ledger.
• add a lambda to get starknet txHash with msg_key as param.

Frontend

• Query CAP instead of the proxy
• Use the lambda to fetch tx_status using starknet sdk. (this is not required but it would be an awesome improvement to user experience)