feat(app): /new-session route for new design (#31457)

packages/app/src/pages/directory-layout.tsx

@@ -10,7 +10,7 @@ import { useSync } from "@/context/sync"
 import { decode64 } from "@/utils/base64"
 import { Schema } from "effect"
 
-function DirectoryDataProvider(props: ParentProps<{ directory: string }>) {
+export function DirectoryDataProvider(props: ParentProps<{ directory: string; draftID?: string }>) {
   const location = useLocation()
   const navigate = useNavigate()
   const params = useParams()
@@ -18,6 +18,8 @@ function DirectoryDataProvider(props: ParentProps<{ directory: string }>) {
   const slug = createMemo(() => base64Encode(props.directory))
 
   createEffect(() => {
+    // A draft lives at /new-session?draftId=… and has no directory segment to normalize.
+    if (props.draftID) return
     const next = sync.data.path.directory
     if (!next || next === props.directory) return
     const path = location.pathname.slice(slug().length + 1)