Migrate module path from kyle/ to mc/ org

All import paths updated from git.wntrmute.dev/kyle/mcias to
git.wntrmute.dev/mc/mcias to match the Gitea organization.
Includes main module and clients/go submodule.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

internal/webauthn/adapter_test.go

@@ -5,7 +5,7 @@ import (
 
 	libwebauthn "github.com/go-webauthn/webauthn/webauthn"
 
-	"git.wntrmute.dev/kyle/mcias/internal/config"
+	"git.wntrmute.dev/mc/mcias/internal/config"
 )
 
 func TestNewWebAuthn(t *testing.T) {