pin h3 version

h3js/h3#1259 broke formdata handling in server functions, so pin h3 to a working version temporarily

Author: schiller-manuel

packages/start-server-core/package.json

@@ -79,7 +79,7 @@
     "@tanstack/router-core": "workspace:*",
     "@tanstack/start-client-core": "workspace:*",
     "@tanstack/start-storage-context": "workspace:*",
-    "h3-v2": "npm:[email protected].6",
+    "h3-v2": "npm:[email protected].5",
     "seroval": "^1.4.1",
     "tiny-invariant": "^1.3.3"
   },