Merge pull request #96 from Hengyu/main

Fix build issues for tvOS and visionOS

Enhances subscription purchase verification logic

Improves the `isPurchased` and `isSubscribed` methods to check if the user has an active subscription to a higher-value product within the same subscription group.

This ensures that the app correctly identifies the user's most valuable active subscription, especially in scenarios involving family sharing or subscription upgrades/downgrades. The `checkSuperceded` parameter is introduced to control this behavior, offering flexibility in subscription status verification.

Adds a new `products(from:)` to retrieve `Product` objects from `ProductId` values.

Adds new `StoreNotification` values to improve logging.

Merge pull request #95 from jixuqianxing/patch-3

fix: Ensure latest verified entitlement is selected when iterating currentEntitlements.

Merge pull request #94 from jixuqianxing/patch-2

fix: Correct Non-Consumable purchase validation logic

Merge pull request #93 from jixuqianxing/patch-1

fix: correct subscription expiration logic

Supports transaction retrieval for older OS versions

Ensures compatibility with older operating systems by providing an alternative method for retrieving current entitlements.

This change addresses the deprecation of `Transaction.currentEntitlement(for:)` in newer iOS and macOS versions, while maintaining functionality on older versions.

Merge pull request #92 from russell-archer/refactor-isPurchased-4subs

Refactors isPurchased logic for subscriptions

Adds product availability management

Introduces functionality to manage product availability, allowing products to be marked as not for sale with a specific reason.

This feature provides methods to add or remove products from the `notForSale` collection, check if a product is for sale, and retrieve the reason why a product is not available. It enhances the user experience by displaying a reason for unavailability instead of a standard purchase button.

Adds "not for sale" product capability

Allows marking products as "not for sale" and displaying a reason.

This introduces a new `NotForSale` struct to represent products that are temporarily unavailable for purchase.
The `StoreHelper` class now includes a `notForSale` property, a collection of `NotForSale` objects.
The `ProductView` now checks if a product is in the `notForSale` collection and displays a message instead of the purchase button if it is.

Merge pull request #90 from lake-of-fire/main

fix crash