Improved password generator logic and added comments

[hamadasyr]

Improved Password Generator Enhancements 🔐✨

1. • Used Python’s built-in string module (ascii_lowercase, ascii_uppercase, digits) instead of hardcoded character strings for better readability and fewer errors.
2. • Ensured initial password complexity by guaranteeing at least one character from each selected category (uppercase, lowercase, digits, symbols) if length allows — making passwords stronger and meeting user expectations.
3. • Shuffled characters randomly after generation to increase randomness and avoid predictable patterns.
4. • Optimized string building by collecting characters in a list and joining them once, improving performance.
5. • Handled very short password lengths gracefully by adjusting character selection logic to avoid errors in edge cases.
6. • Separated user input logic into functions with clear input validation and friendly error messages for better UX and cleaner code.
7. • Added warnings and defaults for empty or insecure length inputs to guide users toward safer choices.
8. • Structured code professionally using main() function and constants, improving maintainability and readability.
9. • Translated all comments and messages to English for wider accessibility.
10. • Overall improvements lead to more robust, secure, readable, and user-friendly password generation.