fix: restore translucent dashboard styling (#6664)

* fix: restore translucent dashboard styling

* fix: restore dashboard widget transparency

* fix: address dashboard review feedback

* fix: apply board opacity to containers

* fix: flatten demo board container

* fix: default board roundness to sm

* fix: restore assistant widget transparency

* Revert "fix: default board roundness to sm"

This reverts commit c235cbdf2b.

* fix: address remaining dashboard review comments

* test: align grid geometry expectations

packages/widgets/src/assistant/component.tsx

@@ -17,7 +17,7 @@ export default function AssistantWidget(props: WidgetComponentProps<"assistant">
   return (
     <Center h="100%" p="md">
       <Stack align="center" gap="xs" ta="center">
-        <ThemeIcon variant="light" color="red" radius="xl" size="lg">
+        <ThemeIcon variant="light" radius="xl" size="lg">
           <IconRobot size="var(--mantine-font-size-xl)" />
         </ThemeIcon>
         <Text size="sm" fw={600}>