DMs no longer show the agent tool calls at the bottom (just "<agent> is typing...)

**Describe the bug**
When in a regular channel, when my agents are working, I can see all the tool calls and thought process at the bottom of the screen. This is super helpful for the experience because I can see an agent working. In DMs, it still just says " is typing..." and sits there for 8, 10, 15 minutes at a time. I can open the activity side window but this is an extra step.

**Steps to reproduce**
Simply ask one of my agents to do something in a DM.

**Expected behavior**
I expect the same as channels, to see the tool calls.

**Version and platform**
- Buzz version: 0.5.17 (and before)
- OS: MacOS

**Logs / additional context**
My agents are NOT agents that are managed from the agents menu, they are Hermes agents on a separate VPS that connect to Buzz using the ACP bridge.

Start by reproducing an ACP-bridge Hermes agent interaction in a DM, then compare it with the same interaction in a regular channel. Inspect the DM message/activity rendering entry point and the existing activity side window; done means DM conversations show the agent tool calls without requiring that extra window, while channel behavior remains unchanged.

Written by the indexing model from the issue text.