Future enhancements for the word guessing game

[vingkan]

Frontend

• Type and delete letters from keyboard
• Show animations when letter results are revealed
• Make game size responsive instead of fixed

Backend

• Fix issue where different API nodes do not know how many guesses you have made
• Fix issue where game logic does not check how many times a letter should appear in the word
• Replace state handling logic in API with stateless game class
• Use sets to make valid word lookups faster
• Expand the list of valid words