app: Initial tabs impl (#28436)

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

@@ -8,6 +8,7 @@ import { LocalProvider } from "@/context/local"
 import { SDKProvider } from "@/context/sdk"
 import { SyncProvider, useSync } from "@/context/sync"
 import { decode64 } from "@/utils/base64"
+import { Schema } from "effect"
 
 function DirectoryDataProvider(props: ParentProps<{ directory: string }>) {
   const location = useLocation()
@@ -40,6 +41,15 @@ function DirectoryDataProvider(props: ParentProps<{ directory: string }>) {
   )
 }
 
+export const ProjectDirString = Schema.String.pipe(Schema.brand("ProjectDirString"))
+export type ProjectDirString = Schema.Schema.Type<typeof ProjectDirString>
+
+export function decodeDirectory(dir: string): ProjectDirString | undefined {
+  const decoded = decode64(dir)
+  if (!decoded) return
+  return ProjectDirString.make(decoded)
+}
+
 export default function Layout(props: ParentProps) {
   const params = useParams()
   const language = useLanguage()
@@ -48,7 +58,7 @@ export default function Layout(props: ParentProps) {
 
   const resolved = createMemo(() => {
     if (!params.dir) return ""
-    return decode64(params.dir) ?? ""
+    return decodeDirectory(params.dir) ?? ""
   })
 
   createEffect(() => {