Override the z-index for the blocks drag layer. At 1000, it will be over everything in the gui other than the navbar itself (monitors on the stage, tutorials, alerts, dropdown menus, etc.)

fixes https://github.com/LLK/scratch-www/issues/2587
and https://github.com/LLK/scratch-gui/issues/4428

changed menu-bar z-index to one more than monitors so drop down menus cover monitors when opened.

Put stage, monitors, add buttons, tooltips, menubar under the block drag layer. Make sure the Extension button is above the toolbox.

* Add mic indicator

* Fix mic indicator position and margin

* Don’t always show indicator, don’t sneaky-enable extension

* Position mic indicator in RTL

* Actually, don’t move indicator in RTL

* Update event name for MIC_LISTENING

* Move mic indicator state into redux

* Move stageSizeToTransform into screen-utils

* Position mic indicator and question at bottom of stage

* Fix pointer events

* JSDOC for stageSizeToTransform

* Pass micIndicator into StageComponent via …props

This bled into normalizing z-indices for the action menus in the z-index.css. The tooltip id was not unique between action menus for ‘suprise’ and ‘paint’, so `mainTooltipId` was used as a prefix to make them unique.