Query parameters are not case-insensitive

[asemindevex]

Ktor Version and Engine Used (client or server and name)
1.3.1, server, ktor-server-netty

Describe the bug
Query parameters claim to be case-insensitive, however they are not. Namely, trying to get a query value for a key which differs only in case from the actual one does not find value.

To Reproduce
Steps to reproduce the behavior:
Using the most basic route to extract a parameter:

fun Route.myRoute() = route("my") {
    get {
        val param = call.request.queryParameters.getOrFail("param")
        call.respondText(param)
    }
}

Calling queryParameters.caseInsensitiveName returns true which is hardcoded.

However, decoder.parameters() returns a regular map, which fails to resolve parameters case-insensitively.

Expected behavior
Query parameters are resolved in the case-insensitive manner.

[cy6erGn0m]

There is no particular specification regulating case-sensitivity, need to look for first

[oleg-larshin]

Please check the following ticket on YouTrack for follow-ups to this issue. GitHub issues will be closed in the coming weeks.