Fix Vitest hanging indefinitely with Vite 6 by using forks pool (#1760)

* Fix vitest hanging by using forks instead of threads pool

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Juice10 <4106+Juice10@users.noreply.github.com>

vitest.config.ts

@@ -9,5 +9,11 @@ export default {
       escapeString: true,
       printBasicPrototype: true,
     },
+    /**
+     * Use forks instead of threads for Vite 6 compatibility
+     * Vite 6 has issues with worker threads not cleaning up properly
+     * causing tests to hang indefinitely
+     */
+    pool: 'forks',
   },
 };