Updated some dependencies to solve act-issue.
After partially bumping dependencies to support MUI 6, all userEvent calls to MUI components seemed to require an additional unnecessary act(...). Updating jsdom, testing libraries, etc. Solved the issue.
Bumping almost all dependencies to their latest versions, required a few smaller changes to due to new ts and eslint versions.
This also includes small fixes to the RichTextEditor because its selection behaviour changes slightly after update.