proxy: Fix misspelled flag value alias, swap names and aliases (#11949)

## Problem

There's a misspelled flag value alias that's not really used anywhere.

## Summary of changes

Fix the alias and make aliases the official flag values and keep old
values as aliases.
Also rename enum variant. No need for it to carry the version now.

proxy/src/binary/proxy.rs

@@ -43,11 +43,12 @@ project_build_tag!(BUILD_TAG);
 use clap::{Parser, ValueEnum};
 
 #[derive(Clone, Debug, ValueEnum)]
+#[clap(rename_all = "kebab-case")]
 enum AuthBackendType {
-    #[value(name("cplane-v1"), alias("control-plane"))]
-    ControlPlaneV1,
+    #[clap(alias("cplane-v1"))]
+    ControlPlane,
 
-    #[value(name("link"), alias("control-redirect"))]
+    #[clap(alias("link"))]
     ConsoleRedirect,
 
     #[cfg(any(test, feature = "testing"))]
@@ -707,7 +708,7 @@ fn build_auth_backend(
     args: &ProxyCliArgs,
 ) -> anyhow::Result<Either<&'static auth::Backend<'static, ()>, &'static ConsoleRedirectBackend>> {
     match &args.auth_backend {
-        AuthBackendType::ControlPlaneV1 => {
+        AuthBackendType::ControlPlane => {
             let wake_compute_cache_config: CacheOptions = args.wake_compute_cache.parse()?;
             let project_info_cache_config: ProjectInfoCacheOptions =
                 args.project_info_cache.parse()?;