you’re running way too old a distro for what you want. debian 12 has its merits as a server, you install it and leave it be and it just works.
what you want - fluidity with power management, dock/undock, etc - although achievable with tweaking this and that isn’t being worked on, not on X, not on debian 12, so it’s not like those things will eventually get there. so you need a semi-modern distro, like ubuntu or fedora or even trixie.
wayland isn’t new, it’s default on a lot of distros since 2021 or so, so you can be sure that your use case was previosly met and solved. costs you nothing to boot e.g. F42 off a USB and try it out (has to be 42 as earlier live sessions default to X11). if you have lots of RAM, add the rd.live.ram
switch so it copies the image to RAM and everything is super-snappy for testing and it doesn’t touch your SSD.
you’re fine using lineageOS with microG and utilising it for cloud messaging, i.e. notifications. the actual content of the notfication doesn’t go through google (or apple), a push message just signals the telegram client there’s activity. then the telegram client wakes up, fetches the message from telegram servers, constructs the notification in-app and then displays it.
google doesn’t have access to the contents of it, but harvests lotsa metadata that microG (as opposed to full-featured play store services) somewhat ameliorates.
having said that, you should make every effort to ditch telegram as well, for a buncha reasons.