feat: add more formatting features on ckeditor

[GretaD]

fixes #11071

list of features added

• [ ] Tables
• [ ] Table Merging
• [ ] Find and replace

Ref: https://ckeditor.com/docs/ckeditor5/latest/features/feature-digest.html

[GretaD]

@nimishavijay i added the 3 listed above, can you please suggest me some more, if you think there should be more. About the order, yes we can change it.

[ChristophWurst]

Adding external images would be good. It will help with https://github.com/nextcloud/mail/issues/11261

[ChristophWurst]

Upload images from computer

what is the difference to https://github.com/nextcloud/mail/pull/6935?

[ChristophWurst]

the situation with readability in dark theme seems to have gotten worse

[GretaD]

the situation with readability in dark theme seems to have gotten worse

fixed

[kesselb]

In the signature editor, the toolbar is overlapping.

[GretaD]

fixed

[GretaD]

@nimishavijay

since now, we have a lot of formatting, how about we we gorup some of them, like for example the text formatting like below, its not same as outlook, but just a suggestion from Daniel :)

[GretaD]

or maybe we do that as a follow up and get this merged?