They have started implementing read-only folders for Immich with the latest release. And it does actually work pretty well.
However it currently is a very manual process via the command line (and not very well documented, especially for docker) and it has limited features as it does not automatically sync new images and does not remove deleted images from its database yet.
Also I would not give too much about the displayed battery health, it can jump all over the place. My car also thinks that my battery is pretty much dead and disabled auto-start/stop. The battery is as fine as it can be, the charging circuit just does not keep track of the charge very well. As long as you don't feel your runtime changing significantly I would not worry much about it.
ProtonDB which separately lists Steam Deck as a separate category. Usually you will find users describing their settings if modification is needed.
ShareDeck specifically for Steam Deck settings.
SteamDeckHQ which has Steam Deck settings as well.
Show Great on Deck as a Browser extension (Firefox/Chrome) which displays all of them on the Steam Store and links directly to the correct subpages.
Thanks, I use Tailscale for various things. But I need direct Wireguard connections in this case. I know I can get it working via command line, I would prefer it on the GUI though or directly in network manager.