Fix CRs for paragraphs with empty first line

[bastianjoel]

resolves #5164
resolves #5165
resolves #5355
reoslves potentionally OpenSlides/OpenSlides#6927

Needs:
OpenSlides/openslides-autoupdate-service#1329
OpenSlides/openslides-backend#3126

Additional Info:
OpenSlides/openslides-meta#307

[Elblinator]

Do not merge yet

[Elblinator]

Please reassign me if approved

[MSoeb]

Found two issue during testing. Already talked with @bastianjoel about it. Full review follows. Need more test data.

• If an instance has an old motion with amendments and change recos in it, an error appears in the console by opening it.
  Error Message: TypeError: Cannot read properties of undefined (reading 'replace')

• In Chrome browser: If several new lines with SHIFT+ENTER are added to an existing motion, the gap between the lines is not visible. The motion looks like no empty lines exists.

[bastianjoel]

@MSoeb The requested changes are fixed now.

[MSoeb]

Found two Issues:

• Projections of motions not possible (I guess it's because of the new projector service) -> projection have their own repository now
• Found a failure in relation to issue #5165 . If I build a motion in the mentioned way and create a change recommendation to line one, two empty lines appears in the CR editor. The motion in normal view and the edtior of the motion instead show only one line. This also happens in empty line three. -> CR should not have two lines. -> is in the second part of my comment

[Elblinator]

p
54 br
1241 br
first br
/p
is creating three lines even thoug hit should create 4 lines

And if you have a CR with a br at the end then there is an additional line to edit which should not be there

editt view (I added the "aaa"