IDE-176 Rework formula editor

[becothas]

• Change the design to look like material 3
• Add buttons for copy and paste
• Remove old copy & paste popup
  IDE-176

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[moberer]

The behaviour that the entire formula is copied when nothing is selected is not intended to be implemented here already, right? - But "linking up" the buttons was already done, from what I can see in the code.

If so, we should probably reformulate https://jira.catrob.at/browse/IDE-177 to account for this.

[dorianpercic]

LGTM!