feat: ibis.udf.analytic.builtin and ibis.udf.table.builtin to allow for more flexibility with engine-specific functions

[tswast]

Is your feature request related to a problem?

In the BigQuery DataFrames library we define several custom operations. These are mostly to expose BigQuery-specific SQL that didn't necessarily make sense to upstream to the BigQuery backend, though I'm sure some of them could find a home. See: https://github.com/googleapis/python-bigquery-dataframes/blob/main/third_party/bigframes_vendored/ibis/backends/bigquery/registry.py and https://github.com/googleapis/python-bigquery-dataframes/tree/main/third_party/bigframes_vendored/ibis/expr/operations

Breaking changes with the operations / expressions API make it difficult for us to keep up with the latest version of Ibis. See the struggle here: https://github.com/googleapis/python-bigquery-dataframes/pull/53

Describe the solution you'd like

A stable way to call custom SQL as part of an ibis expression so that we can have an escape hatch where necessary.

What version of ibis are you running?

6.x

What backend(s) are you using, if any?

BigQuery

Code of Conduct

• [X] I agree to follow this project's Code of Conduct