using `/` on AbsoluteUrl returns a Url

[bblfish]

Describe the bug

Adding a path to an AbsoluteUrl should return a new AbsoluteUrl, not a Url.

From the example below we see that the underlying objects are correct, but the type is not strict enough.

 $ scala-cli repl --amm
Loading...
Welcome to the Ammonite Repl 2.5.4-15-f4a8969b (Scala 3.1.3 Java 19)
@ import $ivy.`io.lemonlabs::scala-uri:4.0.2`
import $ivy.$

@ import io.lemonlabs.uri.AbsoluteUrl
import io.lemonlabs.uri.AbsoluteUrl

@ import io.lemonlabs.uri.typesafe.dsl.*
import io.lemonlabs.uri.typesafe.dsl.*
@ val core = AbsoluteUrl.parse("http://www.w3.org/2001/sw/RDFCore")
core: AbsoluteUrl = AbsoluteUrl(
  scheme = "http",
  authority = Authority(userInfo = None, host = DomainName(value = "www.w3.org"), port = None),
  path = AbsolutePath(parts = Vector("2001", "sw", "RDFCore")),
  query = QueryString(params = Vector()),
  fragment = None
)

@ core / "sub"
res18: Url = AbsoluteUrl(
  scheme = "http",
  authority = Authority(userInfo = None, host = DomainName(value = "www.w3.org"), port = None),
  path = AbsolutePath(parts = Vector("2001", "sw", "RDFCore", "sub")),
  query = QueryString(params = Vector()),
  fragment = None
)

It works correctly with the removeEmptyPathParts method.

@ core.removeEmptyPathParts()
res19: AbsoluteUrl = AbsoluteUrl(
  scheme = "http",
  authority = Authority(userInfo = None, host = DomainName(value = "www.w3.org"), port = None),
  path = AbsolutePath(parts = Vector("2001", "sw", "RDFCore")),
  query = QueryString(params = Vector()),
  fragment = None
)