feat(opencode): add interactive split-footer mode to run (#23557)

packages/opencode/src/cli/cmd/run/runtime.shared.ts

@@ -0,0 +1,17 @@
+type PendingTask<T> = {
+  current?: Promise<T>
+}
+
+export function reusePendingTask<T>(slot: PendingTask<T>, run: () => Promise<T>) {
+  if (slot.current) {
+    return slot.current
+  }
+
+  const task = run().finally(() => {
+    if (slot.current === task) {
+      slot.current = undefined
+    }
+  })
+  slot.current = task
+  return task
+}