Add a points system

[matthewl580]

A clear and concise description of what you want to happen:

Implement a points system within the StudyWeave application.
Users earn points for correctly answering questions in different study modes:
New: 70 points
Learning: 50 points
Mastered: 30 points
Earned points can be used to:
Eliminate incorrect answer choices: Remove one or more incorrect options during a quiz or game.
Skip questions: Skip a difficult question without penalty.
Customize the game experience: Unlock cosmetic items such as:

Different card backgrounds and styles
Background music options
Sound effects
Avatar customization

Describe alternatives you've considered:

Tiered rewards: Award different point values based on the difficulty level of the question or the study mode.
Daily/Weekly Challenges: Introduce daily or weekly challenges to earn bonus points.
Leaderboard Integration: Implement a leaderboard system to encourage competition and motivate users to earn points.
Additional context:

Consider adding a visual representation of the user's points balance within the app.
Provide clear descriptions of the cost of each point-based action.