feat(workbench): expand SCADA monitoring and investigation presentation

src/shared/ui/floating-window-layer.ts

@@ -0,0 +1,32 @@
+let order: string[] = [];
+const listeners = new Set<() => void>();
+let host: HTMLDivElement | undefined;
+
+export const floatingWindowOrder = () => order;
+export const subscribeFloatingWindows = (listener: () => void) => {
+  listeners.add(listener);
+  return () => { listeners.delete(listener); };
+};
+
+export function raiseFloatingWindow(id: string) {
+  if (order.at(-1) === id) return;
+  order = [...order.filter((item) => item !== id), id];
+  listeners.forEach((listener) => listener());
+}
+
+export function removeFloatingWindow(id: string) {
+  if (!order.includes(id)) return;
+  order = order.filter((item) => item !== id);
+  listeners.forEach((listener) => listener());
+}
+
+export function floatingWindowHost() {
+  if (!host?.isConnected) {
+    host = document.createElement("div");
+    // One stacking context keeps windows below dialogs and newly opened menus.
+    host.className = "pointer-events-none fixed inset-0 z-50";
+    host.dataset.floatingWindowLayer = "";
+    document.body.appendChild(host);
+  }
+  return host;
+}