A message beside its open editor stands in the browser too (improvise-1x9h)

The toast hid every status after six seconds, so a refusal the user was
still fixing vanished with its prompt open: su4u's bug on a timer. The
browser now asks the TUI's question. EditorSession moves into
improvise-protocol, ClientState records which editor a status was
written in, and RenderModel::status_stands tells the toast to hold it
until that editor closes.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VdfEGXA7aJ6ftMsCc9PJze

web/app.js

@@ -112,7 +112,7 @@ const shell = createShell({
     // it stays reachable rather than being lost to the cap.
     el.status.title = text;
   },
-  onModel: (text) => toasts.offer(text),
+  onModel: (text, stands) => toasts.offer(text, stands),
   timeoutMs: HANDSHAKE_TIMEOUT_MS,
 });
 // The harness asks whether the watchdog is ARMED, because a negative assertion
@@ -268,7 +268,7 @@ function repaint() {
   el.hint.textContent = model.hint;
   paintHelp(model);
   paintMinibuffer(model);
-  shell.setModel(model.status);
+  shell.setModel(model.status, model.status_stands);
   el.viewName.textContent = model.view_name;
   // The title bar, off the cache `src/draw.rs::draw_title` folds — one
   // derivation, both front ends (improvise-z754, improvise-5jna).