Steam Deck OLED screen auto brightness does not work

[azuwis]

Steps to reproduce auto brightness issue:

1. Ensure auto brightness is enabled in settings
2. At night, turn off all lights
3. Set brightness to min in quick settings
4. Turn on lights
5. The brightness slider won't move, and screen brightness won't automatically change in Jovian-NixOS.

Steps to reproduce screen brightness max issue:

1. At night, turn off all lights
2. Set brightness to min in quick settings
3. Press power button to suspend
4. Press power button to resume
5. The brightness slider won't move, but the screen brightness will set to max, and burn your eyes :(

Edit: The screen brightness max issue no longer exists on current HEAD commit fd13986

Compare to SteamOS closely, SteamOS does not have those issues.

User that run Steam:

$ id
uid=1000(deck) gid=1000(deck) groups=1000(deck),1(wheel),100(users)

Setup, not sure if it's an OLED specific issue.