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/grpcserver/webauthn.go

@@ -11,8 +11,8 @@ import (
 	"google.golang.org/grpc/status"
 	"google.golang.org/protobuf/types/known/timestamppb"
 
-	mciasv1 "git.wntrmute.dev/kyle/mcias/gen/mcias/v1"
-	"git.wntrmute.dev/kyle/mcias/internal/model"
+	mciasv1 "git.wntrmute.dev/mc/mcias/gen/mcias/v1"
+	"git.wntrmute.dev/mc/mcias/internal/model"
 )
 
 // ListWebAuthnCredentials returns metadata for an account's WebAuthn credentials.