feat(web): add Mission Control page layout shell

apps/web/src/components/mission-control/MissionControlLayout.tsx

@@ -0,0 +1,21 @@
+"use client";
+
+import { GlobalAgentRoster } from "@/components/mission-control/GlobalAgentRoster";
+import { MissionControlPanel } from "@/components/mission-control/MissionControlPanel";
+
+const DEFAULT_PANEL_SLOTS = ["panel-1", "panel-2", "panel-3", "panel-4"] as const;
+
+export function MissionControlLayout(): React.JSX.Element {
+  return (
+    <section className="h-full min-h-0 overflow-hidden" aria-label="Mission Control">
+      <div className="grid h-full min-h-0 gap-4 xl:grid-cols-[280px_minmax(0,1fr)]">
+        <aside className="h-full min-h-0">
+          <GlobalAgentRoster />
+        </aside>
+        <main className="h-full min-h-0 overflow-hidden">
+          <MissionControlPanel panels={DEFAULT_PANEL_SLOTS} />
+        </main>
+      </div>
+    </section>
+  );
+}