feat: WIP element Chat intergration

apps/edr-freight-web/backoffice/src/features/chat/chatApi.ts

@@ -0,0 +1,13 @@
+import { api } from "@/auth/http";
+
+/**
+ * Internal chat (Matrix/Element) REST calls. Just the one endpoint — Chat
+ * itself is a separate app (chat.edr.et); this backoffice only ever asks for
+ * a fresh sign-in link into it.
+ */
+export const chatApi = {
+  getSsoUrl: async (): Promise<string> => {
+    const { data } = await api.get<{ url: string }>("/chat/sso");
+    return data.url;
+  },
+};

apps/edr-freight-web/backoffice/src/features/chat/useChatSso.ts

@@ -0,0 +1,19 @@
+import { useQuery } from "@tanstack/react-query";
+
+import { chatApi } from "./chatApi";
+
+export const CHAT_SSO_KEY = ["chat", "sso"] as const;
+
+/**
+ * The login_token this resolves to is single-use and expires in 5 minutes
+ * (Synapse default) — the global `staleTime: 0` (queryClient.ts) already
+ * means every fresh mount of the launch page refetches rather than reusing
+ * a possibly-spent link.
+ */
+export function useChatSso() {
+  return useQuery({
+    queryKey: CHAT_SSO_KEY,
+    queryFn: chatApi.getSsoUrl,
+    retry: false,
+  });
+}