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/ui/csrf.go

@@ -10,7 +10,7 @@ import (
 	"fmt"
 	"sync"
 
-	"git.wntrmute.dev/kyle/mcias/internal/vault"
+	"git.wntrmute.dev/mc/mcias/internal/vault"
 )
 
 // CSRFManager implements HMAC-signed Double-Submit Cookie CSRF protection.