User display name overflows in profile menu

[twassman]

Steps to reproduce

1. Have a user with a reasonably-long display name
2. Open the user's profile in the right menu (e.g. by clicking on the user profile image in a chat)
3. View the user's display name

Outcome

What did you expect?

The user's display name should be displayed in its entirety or truncated with an ellipsis.

What happened instead?

The user's display name overflows, resulting in some of the text being hidden.

Operating system

No response

Browser information

Firefox 137.0b9

URL for webapp

staging.element.io

Application version

Element version: 1.11.96

Homeserver

No response

Will you send logs?

No

[twassman]

Not sure if this is a regression due to #29200.