Introduce more descriptive Cell type and board serialization

[teogor]

Enhance Gameplay Data Management with Board Serialization

This pull request introduces two key improvements:

1. Board Serialization with BoardSerialization.kt:

• Provides functions for efficient encoding and decoding of game boards using base-36 representation.
• Improves data storage and exchange by efficiently representing complex grid structures.
• Offers encodeAsString and decodeAsBoard functions for serialization and deserialization.

2. Refactoring to Clarity:

• Replaces the *.types.Token type alias with a dedicated *.utils.Token type for better readability and understanding.
• More accurately reflects the nature of the values being represented.

Benefits:

• Enhanced data management and efficiency for game boards.
• Clearer code representation and maintainability.
• Potential for future features leveraging efficient encoding.