Configure a Raspberry Compute Module 4 with WIFI and the actual raspian so that the device works as an access point (AP) and as a wireless client/station (STA) at the same time. (Wi-Fi AP/STA concurrency).
The access point should be available as soon as possible after startup.
The WIFI client shall connect to a network as soon as the network is available even when its a while after the boot of the compute module.
A configuration program like RaspAP should not be used.