Dear Maintainer,

The matlab-compatible octave function ode15s is not useable in trixie or experimental, because
the build is not fully configured to use sundials. A typical error message at the octave console is
as follows:

===
error: __ode15__: support for sundials_ida, sundials_nvecserial was unavailable or disabled when Octave was built
===

This error message can be obtained by running the first ode15s example in the octave documentation.

The error persists in the experimental build of 10.2, and can be reproduced by building 10.2
from source on trixie. Of interest is that a backport of 10.2 to bookworm does not display this
behavior; the cited ode15s example runs without error.

I take it that the issue is related to the new version of sundials in trixie. Likely it affects
other functions besides ode15s.