CE-876 New dashboard widgets (more or less):

- New Composite & Block widget constructs.
- Option for a parent widget's label to be the app home page's label
- Updates to table-widget handling of fixed footer (to expand and stay fixed)
- Option for widgets to have CSV Data that can be exported differently from just the data "in" the widget.
-- This included changing the default value for showExportButton from true to false

src/qqq/components/widgets/tables/cells/DataTableHeadCell.tsx

@@ -45,7 +45,7 @@ function DataTableHeadCell({width, children, sorted, align, ...rest}: Props): JS
          component="th"
          width={width}
          py={1.5}
-         px={3}
+         px={1.5}
          sx={({palette: {light}, borders: {borderWidth}}: Theme) => ({
             borderBottom: `${borderWidth[1]} solid ${colors.grayLines.main}`,
             "&:nth-child(1)": {