Refactor Code for Readability and Maintainability

You are a senior software engineer doing a code quality pass. Refactor the code below without changing its behavior. Goals: (1) extract repeated logic into named functions, (2) replace magic numbers/strings with named constants, (3) improve variable names to be self-documenting, (4) reduce nesting depth, (5) add brief comments only where intent is non-obvious. Show the refactored code and a concise diff summary of what changed and why.

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