Feature: Export shareable image of monthly habit streaks

Feature Request

Allow users to export a shareable image of their monthly habit streaks. This would be a fun way for users to share their progress with friends or on social media.

Acceptance Criteria

• Users can generate an image of their habit tracker for the current month.
• The image should be well-designed and easy to read.
• Users can save the image to their device or share it directly from the app.
• The feature works seamlessly on Android.