Add gamma control and night light (#38)

Add configurable night light, smooth gamma transitions, and shell controls. Update documentation and panel tests, and fix portal test startup synchronization.

crates/ferese-ipc/src/lib.rs

@@ -10,6 +10,7 @@ use serde_json::Value;
 
 pub mod events;
 pub mod media;
+pub mod night_light;
 pub mod socket;
 pub mod theme;
 pub mod xwayland;

crates/ferese-ipc/src/night_light.rs

@@ -0,0 +1,10 @@
+use serde::{Deserialize, Serialize};
+
+#[derive(Clone, Debug, Default, Deserialize, Serialize, PartialEq, Eq)]
+pub struct Status {
+    pub enabled: bool,
+    pub temperature: u16,
+    pub supported_outputs: usize,
+    pub active_outputs: usize,
+    pub failed_outputs: usize,
+}