agent_panel: Fix that the `awaiting confirmation` content does cover the hole agent panel (#60992)

# Objective

Currently the sticky `awaiting confirmation` content can grow as big as
the agent panel can go as you can see inside the before picture, that
shows that the full agent panel is coverd by the cofirmation content.
Which is not something we want, because there is no way to see the
actual thread anymore.

**Note**: There was already a fix for this according to this comment but
I could not end up inside that case where it would limit the content.
```
// Cap the content (e.g. a full plan awaiting
// approval) so the floating row can never
// consume the entire panel and squeeze the
// conversation list to zero height, while the
// permission buttons below stay visible.
```

## Solution

The fix is to actually limit the content to a max height of
160px(10rem), which is the value that it was before, but that didn't
work. So I made sure the tool output is now scrollable and it's height
is limited to the specified limit described earlier.

## Testing

You can ask if the agent wants to executes this command, that is just a
very long non existing url. Note, you need to have not auto accept of
permissions enabled to test this bug.

```
curl -sS -v --max-time 15 "https://this-domain-almost-certainly-does-not-exist-abcdefghijklmnopqrstuvwxyz-0123456789-super-duper-extra-long-subdomain-that-nobody-would-ever-register.another-ridiculously-long-and-completely-fake-nonexistent-host-name-9876543210.invalid/api/v1/resources/collections/items/subitems/segment01/segment02/segment03/segment04/segment05/segment06/segment07/segment08/segment09/segment10/segment11/segment12/segment13/segment14/segment15/segment16/segment17/segment18/segment19/segment20/segment21/segment22/segment23/segment24/segment25/segment26/segment27/segment28/segment29/segment30/segment31/segment32/segment33/segment34/segment35/segment36/segment37/segment38/segment39/segment40/segment41/segment42/segment43/segment44/segment45/segment46/segment47/segment48/segment49/segment50/segment51/segment52/segment53/segment54/segment55/segment56/segment57/segment58/segment59/segment60/segment61/segment62/segment63/segment64/segment65/segment66/segment67/segment68/segment69/segment70/segment71/segment72/segment73/segment74/segment75/segment76/segment77/segment78/segment79/segment80/segment81/segment82/segment83/segment84/segment85/segment86/segment87/segment88/segment89/segment90/segment91/segment92/segment93/segment94/segment95/segment96/segment97/segment98/segment99/segment100?param01=value01&param02=value02&param03=value03&param04=value04&param05=value05&param06=value06&param07=value07&param08=value08&param09=value09&param10=value10&param11=value11&param12=value12&param13=value13&param14=value14&param15=value15&param16=value16&param17=value17&param18=value18&param19=value19&param20=value20&param21=value21&param22=value22&param23=value23&param24=value24&param25=value25&param26=value26&param27=value27&param28=value28&param29=value29&param30=value30&param31=value31&param32=value32&param33=value33&param34=value34&param35=value35&param36=value36&param37=value37&param38=value38&param39=value39&param40=value40&param41=value41&param42=value42&param43=value43&param44=value44&param45=value45&param46=value46&param47=value47&param48=value48&param49=value49&param50=value50&the=end"
```

## Self-Review Checklist:

- [x] I've reviewed my own diff for quality, security, and reliability
- [x] Unsafe blocks (if any) have justifying comments
- [x] The content adheres to Zed's UI standards
([UX/UI](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)
and
[icon](https://github.com/zed-industries/zed/blob/main/crates/icons/README.md)
guidelines)
- [x] Tests cover the new/changed behavior
- [x] Performance impact has been considered and is acceptable

## Showcase

**Before** (**Note** the panel is fully coverd by the confirmation
content)

<img width="528" height="817" alt="Screenshot 2026-07-14 at 19 17 53"
src="https://github.com/user-attachments/assets/db0a6b87-2564-4831-9a26-384896ccaefe"
/>


**After** (**Note** the confirmation text is now scrollable again and it
does not cover the full panel anymore)


https://github.com/user-attachments/assets/6c391509-755b-4727-b473-58c21603c4ec

---

Release Notes:

- Agent Panel: Fixed that the sticky `awaiting confirmation` content
could take up the hole agent panel
fa2c3794d0Remco Smits committed on 7/15/2026, 8:47:22 AM· committed by GitHubparentc7b43b2
1 file changedLine totals unavailable