Fix Lint Errors

Core Principle

When fixing lint errors, remove unused code rather than suppressing it. The first specific hint from the linter should guide the fix.

Unused Variables

Rule: Remove unused variables. Do not prefix them with _ to suppress the warning.

Example - Correct:

// Before (lint error: 'unusedVariable' is defined but never used)
function processData(data: string) {
  const unusedVariable = 'test';
  return data.toUpperCase();
}