[Enh]: a method similar to has_operation in Ibis

[e10v]

We would like to learn about your use case. For example, if this feature is needed to adopt Narwhals in an open source project, could you please enter the link to it below?

https://github.com/e10v/tea-tasting

Please describe the purpose of the new feature or describe the problem to solve.

A quote from #1607:

Not all dataframes have a covariance function. For example, pyarrow doesn't have it (though it's still possible to calculate it the same way as tea-tasting does). In this case it would be very useful to have a method similar to Ibis has_operation (example usage). Could you consider adding it as well?

Probably, it could be useful for other methods and downstream packages as well.

Suggest a solution if possible.

No response

If you have tried alternatives, please describe them below.

No response

Additional information that may help us understand your needs.

No response