Sum explicit child budgets and a calibrated wallet overhead, checking u64 bounds.
This is not gas estimation. Calibrate budgets against the target runtime and
workload; there is no universally safe wallet overhead. Root gas reserves
scheduling capacity against the sender's free native-token balance. Storage
deposits are a separate requirement, and funding a target contract does not
sponsor root gas.
Sum explicit child budgets and a calibrated wallet overhead, checking u64 bounds. This is not gas estimation. Calibrate budgets against the target runtime and workload; there is no universally safe wallet overhead. Root gas reserves scheduling capacity against the sender's free native-token balance. Storage deposits are a separate requirement, and funding a target contract does not sponsor root gas.