Store a deposit record for a wallet. Only the wallet owner can call this (require_auth).
fn deposit(
env: soroban_sdk::Env,
wallet: soroban_sdk::Address,
amount: i128,
date: u64,
)
Return the full deposit history for a wallet.
fn get_deposits(
env: soroban_sdk::Env,
wallet: soroban_sdk::Address,
) -> soroban_sdk::Vec
Return the date of the most recent deposit for a wallet. Panics if no deposits exist.
fn get_last_subscription_date(
env: soroban_sdk::Env,
wallet: soroban_sdk::Address,
) -> u64