Open computers from the chat, let bots ask for a take-over, show task progress

- Serve each computer to its owner under /computers/<id>/ (HTTP and
  websockets proxied to the AIO sandbox) and show it in a shared
  ComputerView with browser, terminal and code modes, opened from the
  computers modal or a take-over button in the thread.
- ask_user_to_take_over lets a bot hand a computer to the user for a
  login or captcha; the message gets a take-over button and needs-you,
  and the viewer hands it back with a chat message.
- While a task runs the thread shows "<bot> is working..." with the
  task's latest step; steps read as plain words, not tool names.
- A coordinator with no workers no longer claims to delegate, and bots
  describe started tasks in the first person.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/dict/computer-dict.ts

@@ -87,3 +87,34 @@ export const ComputerMcpExcludedTools = [
     "browser_gui_screenshot",
     "browser_gui_execute_action",
 ] as const;
+
+/**
+ * How the user can open a computer, each one of the AIO sandbox's own
+ * apps at `path` (relative to the computer's address). More of them
+ * (VNC, opencode, codex) can join later.
+ */
+export const ComputerViewModes = [
+    {
+        title: "Browser",
+        value: "browser",
+        path: "browser-ui",
+    },
+    {
+        title: "Terminal",
+        value: "terminal",
+        path: "terminal",
+    },
+    {
+        title: "Code",
+        value: "code",
+        path: "code-server/",
+    },
+] as const;
+
+export type ComputerViewMode = (typeof ComputerViewModes)[number]["value"];
+
+/**
+ * Where the app serves a computer to its owner's browser:
+ * `/computers/<id>/<path>`, proxied to the sandbox (`handleComputerProxy`).
+ */
+export const ComputerProxyPrefix = "/computers";