There should be a guide on adding support for new functions and operators in shapes' WHERE clauses

[alco]

The Electric team can only do so much with our limited resources. However, since Electric is an open-source project, I think many people would love to contribute code to be able to use more data types and/or functions in WHERE clauses of their shape subscriptions. By taking such contributions, we can greatly increase the rate of addition of Postgres functionality to shapes.