feat(theme): per-app accent: pm gives window manifest accent before app runs (display ACCENT, refused after BUFFER); theme::with_accent keeps hue, shifts lightness until contrast passes, else theme accent; tally pink

crates/servers/permission-manager/src/server.rs

@@ -201,6 +201,10 @@ impl PermissionServer {
             true => self.display.and_then(|d| libkos::display::open(d, plan.app.name.as_str().as_bytes())).map(|o| o.window),
             false => None,
         };
+        // Its brand colour too, which the display adapts to the theme.
+        if let (Some(w), Some(accent)) = (window, plan.app.accent) {
+            libkos::display::set_accent(w, accent.0);
+        }
         // Managing others through a copy of this endpoint that can do no
         // more (see `MANAGE_BADGE`).
         let manage = match plan.granted.contains(Capability::Permissions) {