[Feature Request]: Hover tooltip for label attribute in DT columns

### Feature description

Please consider adding a tooltip that shows the label attribute for a column in the data table viewer module: https://github.com/insightsengineering/teal.modules.general/blob/HEAD/R/tm_data_table.R

I love the variable selection dropdown menu which is searchable on the label and the column name. It would be nice to have a toggle to enable folks to see the label on column name hover in the interactive table.

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