convert Inner classes to record classes

[leaf-soba]

• refs:Project: Refactor and unify JabRef OO components #11829
• finish:Inner classes like ComparableMark can be converted to record classes.
• most of them can't change it since there are a method in it or changed the record value, which against the purpose of record.

Mandatory checks

• Change in CHANGELOG.md described in a way that is understandable for the average user (if applicable)
• Tests created for changes (if applicable)
• Manually tested changed features in running JabRef (always required)
• Screenshots added in PR description (for UI changes)
• Checked developer's documentation: Is the information available and up to date? If not, I outlined it in this pull request.
• Checked documentation: Is the information available and up to date? If not, I created an issue at https://github.com/JabRef/user-documentation/issues or, even better, I submitted a pull request to the documentation repository.

[koppor]

Isn't this @param?

[koppor]

Please follow the correct syntax

https://www.oracle.com/technical-resources/articles/java/javadoc-tool.html#format

Discussion at https://stackoverflow.com/a/16138292/873282

If you want, you can search whether checkstyle supports JavaDoc checks or if there are other ways to check for wrong syntax.

Note that IntelliJ should align the text - which is not the case in your thing. If you mark the two lines and press Ctrl+Alt+L, what happens?

[koppor]

I don't see a merge queue option here. All tests are green. Thus, I am directly merging.

[koppor]

@subhramit The update did go into your oo-maintenance branch. I hope, that there won't be any conflicts when merging this branch into main. 😅