pub(crate) async fn handle_host_browser_popup(
__arg0: State<AppState>,
headers: HeaderMap,
__arg2: Json<Value>,
) -> impl IntoResponseExpand description
POST /api/v1/host/browser_popup — a browser pane’s page opened a popup
(docs/specs/SPEC_BROWSER_PANE_POPUPS_ADOPTED_2026_10_08.md). Only the host
calls it, from on_before_popup. Answers {admitted: true, pane} when
srv opened the popup as a pane beside its opener, or {admitted: false, reason}, and the host opens it in the system browser as it always did.