Upgrade mantine monorepo to v7

[maximilianruesch]

Updates the mantine monorepo to v7 and:

• Refactors some components to make the update easier
• Fixes some typos in components
• Fixes some type issues in components
• Updates electron forge from 6.1.1 to 6.4.2 to avoid startup issues
• Swaps out react-beautiful-dnd to @hello-pangea/dnd as an actively maintained fork of the former
• Deactivates delete buttons as we cannot use their positioning, see bug issue: https://projectcanvas.atlassian.net/browse/SCRUM-101