Closes: #14153

Description

This PR addresses some optimizations for logout:

• Deleted all Core Data managed objects in the background context. The changes would then be saved to the persistent container, and the view context would get these changes merged directly from the persistent container. This ensures no discrepancy between the view context and the background context.
• Additionally, upon reset, CoreDataManager also triggers a notification for the reset, which causes the existing result controllers to fetch data again. We have places in the dashboard where we refresh data upon storage reset. To avoid refreshing data in the unauthenticated state, a few checks have also been added for orders, Blaze, and dashboard cards.
• Added a change to DefaultStoresManager to reset sessionManager before updating the state in deauthenticate. This is to avoid an unexpected state where the user is unauthenticated but still has a default store. In [Crash] Attempt to fix crash with magic link login #11373, the AppCoordinator would deauthenticate the app again in this state, triggering an unnecessary reset for CardPresentPaymentAction again.

Steps to reproduce

• Log in to a test store.
• Navigate to Menu > Settings > Log out.
• Confirm logout and check in Xcode console to ensure that there is no more warning about "No processor found for ActionName".
• Confirm that the authenticator is displayed.
• Log in again and confirm that all four tabs are loaded as expected.

Testing information

Tested on simulator iPhone 16 Pro iOS 18.0 and confirmed that logout and login work as expected. The app functions normally after logging in again.

Screenshots

N/A

• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

TODO: @itsmeichigo to update the release notes before merging.

Reviewer (or Author, in the case of optional code reviews):

Please make sure these conditions are met before approving the PR, or request changes if the PR needs improvement:

• The PR is small and has a clear, single focus, or a valid explanation is provided in the description. If needed, please request to split it into smaller PRs.
• Ensure Adequate Unit Test Coverage: The changes are reasonably covered by unit tests or an explanation is provided in the PR description.
• Manual Testing: The author listed all the tests they ran, including smoke tests when needed (e.g., for refactorings). The reviewer confirmed that the PR works as expected on all devices (phone/tablet) and no regressions are added.