Refactor server chat handling by extracting methods

[dingodoppelt]

Short description of changes

This refactors CServer::CreateAndSendChatTextForAllConChannels into three functions for sending messages.
The extracted methods

1. create the full chat message including timestamp and name of the sending client,
2. iterate over all possible channel numbers to
3. send the message text to a channel

As it is now possible to call the function to send a message to a channel directly, the channel number needs to be boundary checked.
A function InRange() was introduced into util.h for that purpose.

CHANGELOG: Refactor server chat handling by extracting methods

Context: Fixes an issue?

Not yet ;)

Does this change need documentation? What needs to be documented and how?
No

Status of this Pull Request

Ready for review
What is missing until this pull request can be merged?

Review, Approval

Checklist

• I've verified that this Pull Request follows the general code principles
• I tested my code and it does what I want
• My code follows the style guide
• I waited some time after this Pull Request was opened and all GitHub checks completed without errors.
• I've filled all the content above

[pljones]

The Java/C# programmer in me wants this as an extension to Comparable<T>, so that

(<Comparable<Int>>32).inRange(0, 100)

returns true. Don't know if C++ can do better than what you've got here, though. (What you should do is constraint T somehow, really.)

[dingodoppelt]

Don't know if C++ can do better than what you've got here, though. (What you should do is constraint T somehow, really.)

This function cannot be called from the outside so I think we should be safe here.
The first placed I searched for range validating functions was the Jamulus source code, then Qt docs because I thought there must be something there. Then I wrote this :) If we don't need it and it might cause issues I'm happy to remove it and do the sanity checks locally.