Sorry this pr conflates a few things together, but I didn't have the energy to split it out only to resolve conflicts down the line.. I think it represents a decent improvement, though, and hopefully none of the functionality is really contentious.

Impressive! A few nitpick comments so far, I'll finish the review later today or tomorrow.

Thanks for the comments 🙏 all very sensible suggestions (especially around that Seq[(Option[String], Seq[(String, String, Option[String])])] 😬 -- took me a few mins to unpick that myself 😅). Have pushed up some fixes to address them

Test failure seems to be... not sure exactly. It ends with

2024-06-22T14:01:01.9474905Z �[0m[�[0m�[0minfo�[0m] �[0m�[0m�[32mAll tests passed.�[0m�[0m
2024-06-22T14:12:30.0226099Z �[34mclientTestServer�[0m ... killing ...
2024-06-22T14:12:40.0077417Z ##[error]Final attempt failed. Timeout of 900000ms hit

-- clientTestServer seems to be related to reStart / mainClass := Some("sttp.tapir.client.tests.HttpServer"), under clientTestServer in the build file? I don't even know if that's what's actually timing out, but tests pass for me locally.

Anyway I think the tests have generally been less flakey of late and I appreciate that, but I mentioned the observation in case it helped shed some light on what the (presumably timing) issue actually is.

@hughsimpson Sorry for the flaky tests, I'm still investigating what's causing these freezes #3827
Don't worry about it, I'll rerun whatever needs rerunning until it succeeds for now.

I guess this part of docs can be updated? https://tapir.softwaremill.com/en/latest/generator/sbt-openapi-codegen.html#json-support

Currently, string-like enums in Scala 2 depend upon the enumeratum library ("com.beachape" %% "enumeratum"). For Scala 3 we derive native enums, and depend on "io.github.bishabosha" %% "enum-extensions" for generating query param serdes. Other forms of OpenApi enum are not currently supported.

Particularly "Other forms of OpenApi enum are not currently supported."?

@hughsimpson Thanks again, looks good!