CLAP: Host misbehaviour crash with "Flush FX when looping" preference activated

[Tas from planet u-he]

Hi guys, we got this from a KVR user, and can confirm it over here.
Tested on M1 MacBook Pro running Sonoma and Reaper 7.05.

To reproduce, use a u-he CLAP plugin, you can get the latest CLAP/MPE beta here on KVR:

https://www.kvraudio.com/forum/viewtopic.php?t=603439

* activate Preferences > Audio > Playback > Flush FX when looping
* load u-he CLAP plugin
* set a loop in Reaper, start playback
* crashes Reaper as soon as it reaches the loop wrap

The plugin logs this at the moment of the crash:

[CLAP] Host called the method clap_plugin_latency.get() on wrong thread! It must be called on main thread!