chore(pm): vendor the Aramesh/PM platform under pm/ (squash of Aramesh/PM @ 91f3271)

The PM panel (PmPanelPage -> iframe /pm/) needs the project-management
platform served at /pm/ on the ERP domain. Source: org repo Aramesh/PM,
branch feature/project-management-platform. Update via:
git subtree pull --prefix=pm aramesh-pm feature/project-management-platform --squash

pm/frontend/src/main.tsx

@@ -0,0 +1,28 @@
+import React from "react";
+import ReactDOM from "react-dom/client";
+import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
+import { Toaster } from "sonner";
+import App from "./App";
+import { ErrorBoundary } from "./components/ErrorBoundary";
+import "./index.css";
+
+const queryClient = new QueryClient({
+  defaultOptions: {
+    queries: {
+      staleTime: 30_000,
+      retry: 1,
+      refetchOnWindowFocus: false,
+    },
+  },
+});
+
+ReactDOM.createRoot(document.getElementById("root")!).render(
+  <React.StrictMode>
+    <QueryClientProvider client={queryClient}>
+      <ErrorBoundary>
+        <App />
+      </ErrorBoundary>
+      <Toaster position="top-center" dir="rtl" richColors closeButton />
+    </QueryClientProvider>
+  </React.StrictMode>,
+);