[BUG] Doesn't utilize decky-loader's new settings location

[jurassicplayer]

Describe the bug Decky-loader now has environment variables and a new default settings location for plugins. Need to convert to using the new location and env variables and add migration path.

To Reproduce

• [x] Reproducible after a full restart Steps to reproduce the behavior:
  1. Boot
  2. Note that settings read is located at ~/homebrew/settings/decky-autosuspend.json

SteamOS Update Channel: [ ] Stable [ ] Beta [x] Preview

Decky Loader:

• Loader Version: v2.5.3-pre3
• Plugin Version: v1.3.4

Other plugins installed

• decky-autoflatpak

[jurassicplayer]

Fixed with c326aaf39e93bb5a89bdf52c1bcde119134103bc