Returns the owner of the given token_id, if it exists.
fn owner_of(env: soroban_sdk::Env, token_id: u32) -> Option
Mints a new Master Avatar NFT. Requirements:
to must authorize the invocation (via require_auth)fn public_mint(env: soroban_sdk::Env, to: soroban_sdk::Address) -> u32
Returns the total number of minted avatars.
fn total_minted(env: soroban_sdk::Env) -> u32