Add match detection and jewel dropping functionality
This commit implements the core matching logic for the gem matching game:
- Added isDropping flag to prevent concurrent drop operations
- Implemented checkMatches() function to detect horizontal and vertical matches of 3+ jewels
- Added destroyMatchedJewels() function to animate and remove matched jewels
- Implemented dropJewels() function to handle jewel dropping after matches are cleared
- Integrated match checking into the swap completion callback
- Added proper animation sequences with tweens and delayed calls for smooth gameplay
The changes enable the core gem matching mechanics where matched jewels are destroyed, remaining jewels fall down to fill gaps, and new matches are automatically detected and processed.
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- Increased starting rows from 2 to 5 for larger initial grid
- Added selectedJewel and swapWithJewel properties for tracking selections
- Enhanced world bounds to provide better collision detection area
- Implemented click handling for jewels with selection/deselection logic
- Added adjacent jewel checking and swapping functionality with animations
- Included visual feedback through scaling tweens when selecting jewels
- Implemented isSwapping flag to prevent concurrent interactions during swaps
- Disabled interactivity during swap animations and re-enabled afterward
- Removed gravity from arcade physics for puzzle game behavior
The changes implement core gameplay mechanics for a match-three style puzzle game where players can select jewels, check adjacency, and swap positions with visual feedback.