Bug Description

When using message(action=read, threadId=X) for Slack, it returns channel messages instead of the actual thread replies.

Steps to Reproduce

1. Have a Slack thread with replies (e.g., thread_ts=1770453772.915809 with reply_count: 2)
2. Call:

{
  "action": "read",
  "channel": "slack",
  "channelId": "C039PUGE13P",
  "threadId": "1770453772.915809",
  "limit": 10
}

3. Response contains channel root messages, NOT the thread replies

Expected Behavior

When threadId is provided, the response should return messages from that specific thread (using Slack's conversations.replies API).

Actual Behavior

Returns channel messages (same as without threadId), ignoring the thread context.

Workaround

Currently using a script that calls Slack API directly:

curl -s "https://slack.com/api/conversations.replies?channel=${CHANNEL}&ts=${THREAD_TS}&limit=${LIMIT}" \
    -H "Authorization: Bearer $SLACK_TOKEN"

Impact

This breaks agent context when responding in Slack threads - the agent cannot see previous replies in the conversation, leading to hallucinations and context-blind responses.

Environment

• OpenClaw version: 2026.2.6-3
• Channel: Slack