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/docker/styles.css

@@ -0,0 +1,5 @@
+/* Keep Docker rows translucent so board wallpaper and the inherited item opacity remain visible. */
+.homarr-data-table.docker-table {
+  --mantine-datatable-background-color: transparent !important;
+  --mantine-datatable-striped-color: transparent !important;
+}