Ambire Wallet is a smart wallet, meaning that each user account is a smart contract.
This allows your transactions to only be signed messages that authorize your actions, while someone else will actually run the transaction on-chain and pay for the gas, trustlessly. This concept is also known as "meta transactions".
Rest assured, nothing can be done from your account without your signature, however this is an example of the versatility that smart contracts offer: a transaction can incorporate another transaction related to gas fees, meaning someone else can pay for your gas and be reimbursed in a different way - in this case, with a stablecoin payment that's part of the actual transaction.