Generated types for performance

We should consider making a generated type provider. There are previous closed threads (https://github.com/fsprojects/FSharp.Data.SqlClient/issues/61, ) that have focused on C# friendliness, which is a very good goal, but this is about performance at design-time.

The performance advantage of genreated types is that it can use the build system and therefore run at predictable times and manually. A very small project can use the FSharp.Data.SqlClient with a reference to a database connection, and then be built. Any referencing project will get usable intellisense performance without the performance issues that plague this library. https://github.com/fsprojects/FSharp.Data.SqlClient/issues/343 . It would also address cases where the type provider does not know when to update types, since there is no way to control this manually at present https://github.com/fsprojects/FSharp.Data.SqlClient/issues/329 .

This workflow would operate similarly to SQL+ .NET, i.e. providing a way to get dotnet code from an sql project.

Start by reading the linked issues 61, 343, and 329, then compare the proposed workflow with SQL+ .NET. Done would require an agreed design for generated types, their build-time execution, and how the resulting .NET code is consumed.