0.4.1 release note overstates user-defined-tool availability (403 on usegalaxy.org)

The 0.4.1 release note says "User-defined tools run again on Galaxy 26.0 servers." A user reasonably read that as "I can use UDTs on my usegalaxy.org connection," but creating a UDT there fails with:

```
403: User is not allowed to run unprivileged tools (err_code: 403005)
```

UDTs depend on server/account permissions and aren't generally enabled for unprivileged users on public servers, but the note reads as broad availability. Suggest clarifying the wording (and/or surfacing a clearer in-app message on the 403) so users know UDTs require server-side permission.

Minor / docs.