Refactor Cart into checkerboard table

Closes: #173 (closed)

Removes clear all feature from: #233

This one improves focus behavior in the cart, moving cart items and deleting items from the cart.

clive/__private/ui/widgets/clive_checkerboard_table.py

@@ -89,6 +89,10 @@ class CliveCheckerBoardTableCell(Container):
         else:
             yield Static(self._content)
 
+    def update_content(self, content: str) -> None:
+        self._content = content
+        self.query_one(Static).update(self._content)
+
 
 class CliveCheckerboardTableRow(CliveWidget):
     """Row with checkerboard columns."""