Replied messages show as UTDs in replies, even if the original is now decryptable.

### Steps to reproduce

1. Receive a UTD
2. Receive a reply to it
3. Clear cache to fix the UTD
4. Observe the quoted UTD in the reply is still undecryptable - looks like a caching problem.
5. Clearing cache *again* - this time it's fixed.

### Outcome

#### What did you expect?

Don't keep displaying UTDs in quoted replies once they're resolved.

#### What happened instead?

UTD is cached in the quoted reply.

### Your phone model

S10

### Operating system version

_No response_

### Application version and app store

0.4.17-nightly

### Homeserver

matrix.org

### Will you send logs?

Yes

### Are you willing to provide a PR?

No

Reproduce the sequence by receiving a UTD, receiving a reply, clearing the cache, and checking the quoted message. Trace the quoted-reply rendering and message cache handling to find why the old UTD remains; done means the quote becomes decryptable after the original message is resolved without requiring a second cache clear.

Written by the indexing model from the issue text.