feat: pin sessions to workspace revisions

frontend/src/shell/SteerInput.test.tsx

@@ -8,6 +8,7 @@ import { useSessionStore } from "../store/sessionStore";
 import { ComposerFooter, ContextGauge, SteerInput } from "./SteerInput";
 
 beforeEach(() => {
+  localStorage.clear();
   server.use(
     http.post("http://localhost:8787/sessions/:id/steer", () =>
       new HttpResponse(null, { status: 204 }),
@@ -15,6 +16,25 @@ beforeEach(() => {
   );
 });
 
+test("new sessions send the browser-selected workspace, model, provider, and thinking", async () => {
+  let body: unknown;
+  localStorage.setItem("thothii.workspace-registry.v1.preferences", JSON.stringify({
+    workspaceId: "psd-clinical", provider: "zai", model: "glm-5.2", thinking: "high",
+  }));
+  server.use(http.post("http://localhost:8787/sessions", async ({ request }) => {
+    body = await request.json();
+    return HttpResponse.json({ id: "s1" });
+  }));
+  render(<SteerInput sessionId={null} />);
+
+  await userEvent.type(screen.getByRole("textbox", { name: /new question/i }), "q");
+  await userEvent.click(screen.getByRole("button", { name: /send/i }));
+
+  await waitFor(() => expect(body).toEqual({
+    question: "q", workspaceId: "psd-clinical", provider: "zai", model: "glm-5.2", thinking: "high",
+  }));
+});
+
 test("renders a text input and submit button", () => {
   render(<SteerInput sessionId="s1" />);
   expect(screen.getByRole("textbox")).toBeInTheDocument();