Improve code readability

[Prayag2]

This PR does a few things to improve code readability so that's it's easier to develop and contribute to the application.

Changes

• Split the code into three files, funcs.py, consts.py, and app.py.
• Created two functions ask_gpt and type_message to reduce repeated lines of code.
• Added docstrings to every function so that future contributors can understand the code more easily.
• Refactored the code according to PyLint's suggestions to follow best practices (pylint score is above 9.5).
• Formatted the code using black formatter for Python to improve code consistency.
• Added a .gitignore file to ignore pycache and venv.
• It will now use the OS environment variables to get the API keys. Users can provide their API keys in the .env file.

[Prayag2]

Pls don't forget to add hacktoberfest-accepted label XD

[Prayag2]

I've fixed the recursion problem.

[programmingninjas]

Great work @Prayag2 👍

[Prayag2]

Bery noice :smiley_cat: Thank you for merging!!