Support for OSTREE-based distributions

[PilotGuy772]

Fixes #180
Fixes #114
Fixes #49

EnvyControl is configured right now to put udev rules in /lib/udev. The problem with this is that /lib/udev is distinctly intended for udev rules from the distribution. It is NOT meant to be manipulated so heavily. Instead, system admins ought to use /etc/udev to put custom rules.

This ordinarily isn't a problem for EnvyControl because most distros don't care if you modify /lib/, but immutable distros like Fedora Silverblue do care. /lib/ is not writable, but /etc/ is. There's a reason for that.

This PR changes the udev directory to /etc/udev/, but everything still works as expected with this change. I also added logic to check if the distribution uses ostree by checking for /ostree and /sysroot/ostree, which are the two places where you would usually find the ostree directory. My amateur testing on Bluefin has shown that switching between integrated and hybrid modes works perfectly.

[PilotGuy772]

@bayasdev I added logic to cleanup() in my latest commit to address your concerns. I just have statements to check for EnvyControl's udev rules in /lib/udev/rules.d and remove them if they exist.

[bayasdev]

@PilotGuy772 I think we could do something like this instead

    # define list of files to remove
    to_remove = [
        BLACKLIST_PATH,
        UDEV_INTEGRATED_PATH,
        UDEV_PM_PATH,
        XORG_PATH,
        EXTRA_XORG_PATH,
        MODESET_PATH,
        LIGHTDM_SCRIPT_PATH,
        LIGHTDM_CONFIG_PATH,
        # legacy paths
        '/etc/X11/xorg.conf.d/90-nvidia.conf',
        '/lib/udev/rules.d/50-remove-nvidia.rules',
        '/lib/udev/rules.d/80-nvidia-pm.rules'
    ]

    # remove each file in the list
    for file_path in to_remove:
        try:
            if os.path.exists(lfile_path):
                os.remove(file_path)
                logging.info(f"Removed file {file_path}")
        except OSError as e:
            # only warn if file exists (code 2)
            if e.errno != 2:
                logging.error(f"Failed to remove file '{file_path}': {e}")

[bayasdev]

could you please remove the redundant comments?

[bayasdev]

why was this changed?

[bayasdev]

@PilotGuy772 please take a look at the comments I left, and thank you for adding OSTree support to EnvyControl as it was a frequently requested feature 🙌🏼

[PilotGuy772]

@bayasdev All done (I think)

[bayasdev]

LGTM

[bayasdev]

Thanks @PilotGuy772