ui/hooks: useMaybeClanUri init hook

Needed for pre-rendering the cube scene with clanURI = null
When it later receives a value scene will get populated without completely re-rendering

pkgs/clan-app/ui/src/hooks/clan.ts

@@ -1,6 +1,6 @@
 import { callApi } from "@/src/hooks/api";
 import { addClanURI, setActiveClanURI } from "@/src/stores/clan";
-import { Params, Navigator } from "@solidjs/router";
+import { Params, Navigator, useParams } from "@solidjs/router";
 
 export const selectClanFolder = async () => {
   const req = callApi("get_clan_folder", {});
@@ -27,3 +27,19 @@ export const navigateToClan = (navigate: Navigator, uri: string) => {
 export const clanURIParam = (params: Params) => {
   return window.atob(params.clanURI);
 };
+
+export const useMaybeClanURI = () => {
+  const params = useParams();
+
+  if (!params.clanURI) {
+    return null;
+  }
+
+  const clanURI = clanURIParam(params);
+
+  if (!clanURI) {
+    throw new Error("Could not decode clan URI from params: " + params.clanURI);
+  }
+
+  return clanURI;
+};