Read Mode catalog: Page Color is live

#4182 was written before view.readPageColor (#4172) landed, so the
progress log listed Page Color as missing. The catalog test checks it
is live.

crates/engine/src/catalog.rs

@@ -605,5 +605,6 @@ mod tests {
         );
         let reg = crate::cmd::registry();
         assert!(reg.get("view.readColumnWidth").is_some(), "Column Width counts as live");
+        assert!(reg.get("view.readPageColor").is_some(), "Page Color counts as live");
     }
 }