feat: Refactor Task Manager: Remove habit management feature

[Joe-Ortiz]

• Updated manifest and package descriptions to remove references to habits and gamification.
• Removed habit-related properties and methods from app.ts and storage.ts.
• Cleaned up associated tests in storage.test.ts to reflect the removal of habit management.

Copilot Summary

This pull request removes the habit tracking and gamification features from Task Manager Pro, simplifying the application to focus on task, project, and finance management. The changes update the user interface, documentation, CSS, and end-to-end tests to reflect the removal of these features.

Feature Removal and UI Updates:

• All habit tracking functionality and related UI elements (such as the habits tab, habit cards, and incomplete habits list) have been removed from index.html and associated CSS styles. [1] [2] [3]
• The gamification system, including user level, streaks, and rewards shop, has been removed from both the UI (index.html) and the documentation (README.md). [1] [2] [3]

Documentation Updates:

• The README.md has been updated to remove references to habit tracking and gamification, and to clarify the current features of the app. [1] [2] [3] [4]

Testing Updates:

• End-to-end tests related to habits and gamification have been removed from e2e/app.spec.ts, including tests for habit CRUD operations and header stats. [1] [2] [3] [4] [5]

Styling Cleanup:

• CSS styles related to habits, emoji selectors, and header stats have been removed from css/styles.css to clean up unused styles. [1] [2] [3] [4]

Meta and Navigation Adjustments:

• The app’s meta description and navigation have been updated to reflect the removal of habit tracking. [1] [2]