fix(l10n): Nicer capitalization for generic messages

[kra-mo]

Follow-up to #54202

Summary

Actually seeing these in production made me realize that they look awkward without a capital letter at the start.

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Documentation (manuals or wiki) has been updated or is not required
• Labels added where applicable (ex: bug/enhancement, 3. to review, feature component)

[rakekniven]

Hello @kra-mo ,

We currently have a colorful mix on this topic in our strings.

Are your changes based on a known specification?
https://www.grammarly.com/blog/punctuation-capitalization/capitalization-after-colons/

https://commission.europa.eu/document/download/c45f5b70-2d0e-4da7-b181-b5fe3a16c4bb_en says in chapter 2.7 (page 13):
In Irish/British usage, colons do not require the next word to start with a capital.

Same here:
https://www.grammarbook.com/punctuation/colons.asp

Do you know of any specifications that we could use in our guidelines?

[rakekniven]

See my comment.
Let us define a rule before applying such changes.

[kra-mo]

My only thought was that since the string before it is inserted dynamically and is in a different mood, it could never form a complete sentence with what is after it so it just felt very weird to not break it up more.

I don't think capitalization after colons should be a rule in general, this is just a one-off because of the weird way this sting is constructed. But I'd love to get rid of these strings and replace them with more natural ones in the future.