SAK-50309 Library upgrade rich text editor to CKEditor 5

[adrianfish]

https://sakaiproject.atlassian.net/browse/SAK-50309

[adrianfish]

I've submitted this PR as a draft so that people can start to take a look if they want. You need to build webcomponents and restart tomcat. Then use the Conversations tool and add a topic. The description field there is using the ck5 mode of sakai-editor. Just kick the tires, if you have the time. Try dark mode. One big thing still missing is elfinder, which I'll start looking at when I've attended to some of my other responsibilities.

[jonespm]

Awesome! Will check this out soon. Looks like at least elfinder has a pattern for this that you may have seen. https://github.com/Studio-42/elFinder/wiki/Integration-with-CKEditor-5

I added a comment to the SAK with some other plugins we'll have to address and others we can either drop or will have to re-do from scratch.