feat(docs): Add documentation for using records and typedef

[Asncodes-80]

This commit introduces a new section in the documentation showcasing the combination of Dart's record types and typedef to create a simple, reusable data structure for dynamic UI rendering.

This approach was originally shared as an answer on Stack Overflow in Spring 2023 to the question: "Is there anything like a struct in Dart?" (https://stackoverflow.com/a/76391196/12158825). The solution received highly positive feedback via emails and comments, highlighting its usefulness for developers.

This feature is now documented as a recommended approach for developers aiming to write cleaner and more maintainable Dart code that wasn't mentioned before.

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• This PR follows the Google Developer Documentation Style Guidelines — for example, it doesn't use i.e. or e.g., and it avoids I and we (first person).
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  Waiting for the further feedback.

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