GFX control, no-tokio, no-async, dbus client refactor

- Working gfx modes <iGPU only, dGPU only, or hybrid>
- Add signal for gfx vendor change and make CLI wait for signal
- Add polling for led brightness to save to config
- Move daemon to zbus crate
- dbus client refactor
- Further dbus methods and updates
- Add basic notification user daemon and systemd service

ctrl-gfx/Cargo.toml

@@ -0,0 +1,19 @@
+[package]
+name = "ctrl-gfx"
+version = "2.0.0"
+license = "MPL-2.0"
+readme = "README.md"
+authors = ["Luke <luke@ljones.dev>"]
+description = "Fine control of laptop GPU"
+edition = "2018"
+
+[dependencies]
+sysfs-class = "^0.1.2"
+log = "^0.4"
+
+zbus = { version = "1.1.1", optional = true }
+zvariant = { version = "2.2.0", optional = true }
+
+[features]
+default = ["use-zbus"]
+use-zbus = ["zbus", "zvariant"]