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/types/index.ts

@@ -277,6 +277,10 @@ export type PagePropsType = {
      * The open bot's computers, the one it's on first.
      */
     bot_computers?: BUN_SQLITE_COBBLE_COMPUTERS[] | null;
+    /**
+     * The open bot's active task and what its job has done so far.
+     */
+    bot_task?: BotTaskWithSteps | null;
     environment?: string;
     has_password?: boolean;
     backups?: DbBackup[] | null;