Update script.js

[Imran-imtiaz48]

trafficstars

Key Improvements:

1. Function Clarity: Functions are named according to their purpose (getHistoryElement, printHistory, getOutputText, printOutput).
2. Consistent Variable Naming: Variables are named more descriptively (calculationPerformed instead of f, operators instead of lst).
3. Error Handling: Improved error handling in the eval block to ensure robustness.
4. Conditional Logic: Simplified and clarified conditional logic for button clicks.
5. Comments: Added comments for clarity and to explain complex logic or edge cases. This refactoring improves readability, reduces redundancy, and enhances maintainability, adhering to more professional coding standards.