displayname change prior to join incorrectly renders as "x joined the room"

### Steps to reproduce

1. @benparsons made an encrypted room
2. @benparsons invited me to the room
3. @benparsons changed his display name
4. I joined
5.

### Outcome

#### What did you expect?
- To see the event rendered correctly

#### What happened instead?
- as per screenshot - rendered as a join

### Operating system

Mac

### Application version

Element version: 1.12.25 Crypto version: Rust SDK 0.18.0 (16a138b), Vodozemac 0.10.0

### How did you install the app?

website

### Homeserver

lant.uk

### Will you send logs?

Yes

Reproduce the encrypted-room scenario described in the issue, including changing the display name before joining, then inspect the event-rendering path responsible for the displayed membership message. Done means the event is rendered correctly as the display-name change rather than as “x joined the room”; no specific file or test is named in the issue.

Written by the indexing model from the issue text.