style: simplify panel titles

Clean up UI panel titles by removing redundant keyboard hints that are
already present in the app's status bar or are no longer needed.

Co-Authored-By: fiddlerwoaroof/git-smart-commit (unsloth/gemma-4-31B-it-GGUF:UD-Q5_K_XL)

src/ui/category_panel.rs

@@ -49,7 +49,7 @@ impl<'a> Widget for CategoryPanel<'a> {
         let is_active = matches!(self.mode, AppMode::CategoryPanel) || is_item_add || is_cat_add;
 
         let (border_color, title) = if is_active {
-            (Color::Cyan, " Categories  n:new  d:del  Space:axis ")
+            (Color::Cyan, " Categories ")
         } else {
             (Color::DarkGray, " Categories ")
         };