feat: implement Checkers with forced captures and promotion rules

[pheobeayo]

fixes and closes #67

Implemented the Checkers with Forced captures and Promotion rules

• Initialized a standard Checkers board.
• Where the current player submits a move.
• The contract validates ownership, movement legality, and mandatory captures.
• The contract updates board state, removes captured pieces, and promotes when applicable.
• The Turn advances or the game ends if a win condition is met

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[salazarsebas]

Hey @pheobeayo ,
Please move the workflow to the main root directory; otherwise, it won't run.

[pheobeayo]

Hey @pheobeayo , Please move the workflow to the main root directory; otherwise, it won't run.

Done

[salazarsebas]

Hey @pheobeayo , please fix the workflow errors

[salazarsebas]

LGTM