fix: gate typed chat stops

ui/src/pages/chat/chat-commands.ts

@@ -95,7 +95,7 @@ function currentSessionAccessSnapshot(
   };
 }
 
-function requireChatSessionAction(
+export function requireChatSessionAction(
   host: ChatCommandHost,
   action: "abort" | "compact" | "reset",
 ): boolean {

ui/src/pages/chat/chat-send-submit.ts

@@ -9,7 +9,11 @@ import {
   getChatAttachmentDataUrl,
   releaseChatAttachmentPayloads,
 } from "./attachment-payload-store.ts";
-import { dispatchChatSlashCommand, shouldQueueLocalSlashCommand } from "./chat-commands.ts";
+import {
+  dispatchChatSlashCommand,
+  requireChatSessionAction,
+  shouldQueueLocalSlashCommand,
+} from "./chat-commands.ts";
 import type { ChatState } from "./chat-history.ts";
 import {
   admitQueuedMessageForSession,
@@ -213,6 +217,9 @@ export async function handleSendChat(
       isChatStopCommand(message) &&
       (message.trim().startsWith("/") || hasAbortableSessionRun(host))
     ) {
+      if (!requireChatSessionAction(host, "abort")) {
+        return;
+      }
       if (messageOverride == null) {
         recordNonTranscriptInputHistory(host, message);
       }

ui/src/pages/chat/chat-send.test.ts

@@ -8688,6 +8688,28 @@ describe("handleAbortChat", () => {
     },
   );
 
+  it("blocks a typed stop before aborting when the operator lacks write scope", async () => {
+    const host = makeHost({
+      requestHandlers: {},
+      chatRunId: "run-main",
+      chatMessage: "/stop",
+      hello: {
+        type: "hello-ok",
+        protocol: 4,
+        auth: { role: "operator", scopes: ["operator.read"] },
+        features: { methods: ["chat.abort"] },
+      },
+      sessionKey: "agent:main",
+    });
+
+    await handleSendChat(host);
+
+    expect(host.request).not.toHaveBeenCalled();
+    expect(host.lastError).toBeTruthy();
+    expect(host.chatError).toBe(host.lastError);
+    expect(host.chatMessage).toBe("/stop");
+  });
+
   it("queues the active run abort while disconnected", async () => {
     const client = { request: vi.fn() } as unknown as NonNullable<ChatHost["client"]>;
     const host = makeHost({