Allow selecting multiple sheets as active

[imirkin]

Description

Excel allows selecting multiple sheets as active, by shift- (or ctrl-) clicking on the tabs. This comes out in the resulting xlsx as

  <sheetViews>
    <sheetView tabSelected="1" workbookViewId="0"/>
  </sheetViews>

in multiple sheet files. There's already a SetActiveSheet and GetActiveSheetIndex but they pre-suppose that only a single sheet is active at a time. This is a very minor feature, but helpful for e.g. printing multiple sheets without having to first select them.

Additional context

No response

Validations

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