grok worker launches in single-turn mode and exits without editing

[nikhilachale]

Problem

When spawning a grok worker, AO launches Grok with -p <prompt>. On Grok 0.2.64, -p / --single means single-turn
mode: Grok prints a response to stdout and exits.

As a result, AO workers using Grok do not stay in an interactive coding session and may make no file changes.

Example

Session: renz-ui-51
Task: add good morning message in hero section
Harness: grok

The tmux pane showed only:

I'll find the hero section in the codebase and see how it's structured so we can add a good morning message.
The hero already has a static greeting — I'll check other landing files and styles to see if we should make it time-based or
more prominent.

Then Grok returned to the shell prompt. git status was clean.

## Root Cause

AO currently builds the Grok launch command as:

grok --no-auto-update -p "<task>"

But grok -h documents:

-p, --single <PROMPT>
  Single-turn prompt. Prints the response to stdout and exits

## Expected Behavior

A Grok worker should start an interactive coding session and continue running so it can inspect files, edit code, run checks,
and respond to follow-up messages.

## Suggested Fix

Change the Grok adapter to pass the initial task as the positional prompt instead of using -p:

grok --no-auto-update "<task>"

Keep -p only for an explicit one-shot/headless mode, if AO supports that separately.

## Impact

Grok workers can appear idle/alive in AO because the tmux shell remains open, but the Grok process has already exited and no
work is being performed.