chore: audit components

crates/theme/src/source.rs

@@ -12,6 +12,16 @@ pub(crate) trait ThemeSource: 'static {
     fn label(&self) -> &'static str;
 }
 
+/// Narrows an f64 color component to f32, clamping to the 0..=1 range and
+/// mapping non-finite values to 0.0 rather than truncating garbage silently.
+pub(crate) fn narrow_component(value: f64) -> f32 {
+    if value.is_finite() {
+        value.clamp(0.0, 1.0) as f32
+    } else {
+        0.0
+    }
+}
+
 #[cfg(target_os = "macos")]
 pub(crate) fn platform_source() -> Box<dyn ThemeSource> {
     Box::new(macos::MacosSource::default())