Returns the resource-pressure level for key (config.gas.features[key]).
Returns GasLevel.Normal with zero overhead when the feature factor is 0 or absent
and no gas plugins are registered (plugins are always consulted and may escalate any key).
Measured from the start of the enclosing contingent, against the thresholds configured for key
(see GasThresholdSpec), not one allowance shared by everything the analyzer does.
A view with a fresh contingent, measured from this call, for one operation to run against.
The enclosing bounds still apply, overrides winning over them. Derives a new object rather than
mutating this one, so it is safe for nested and concurrent work.
Optionaloverrides: GasOverrides
The gas context as the owner of the analyzer sees it, reachable via
analyzer.context().gas. Adds the operations that restart a contingent to ReadOnlyFlowrAnalyzerGasContext.