Bump vite to ^6.4.3 in test

Fixes both open security alerts (server.fs.deny bypass on Windows,
launch-editor NTLMv2 hash disclosure) within vite 6.x, avoiding the
vite 8 major jump that breaks the vite-app integration test.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: paberr

test/package-lock.json

@@ -16,6 +16,6 @@
     "@types/node": "^22.10.1",
     "serve": "^14.2.6",
     "shx": "^0.3.4",
-    "vite": "^6.4.2"
+    "vite": "^6.4.3"
   }
 }