Update reward rate card flow and BillingClient logic

[jsyjbaba]

Update reward rate card flow and BillingClient logic

[gemini-code-assist]

Code Review

This pull request implements a mechanism to check and restore pending or unacknowledged purchases when the game starts or enters the foreground. It also updates project dependencies in the build configuration. The review identified two key issues: first, calling the purchase check immediately in Init() is ineffective because the asynchronous auto-login has not yet completed; second, the receipt processing loop incorrectly uses TransactionId instead of ReceiptId for finalization and redundantly calls FinalizePurchase inside the inner loop.