fix: badge count not resetting when notifications are cleared

[nan-li]

Description

One Line Summary

Reset cached badge count value when notifications are cleared.

Details

Motivation

When using badge type "Increase", the cached badge value (ONESIGNAL_BADGE_KEY) in shared UserDefaults was not explicitly reset to zero in clearBadgeCount:fromClearAll:. If the swizzled badge setter did not fire, the NSE would read the stale cached value and increment from it, producing an incorrect badge count.

Scope

badges

Testing

Unit testing

Manual testing

Tested on iPhone iOS 26.3

Affected code checklist

• Notifications
  • Display
  • Open
  • Push Processing
  • Confirm Deliveries
• Outcomes
• Sessions
• In-App Messaging
• REST API requests
• Public API changes

Checklist

Overview

• I have filled out all REQUIRED sections above
• PR does one thing
• Any Public API changes are explained in the PR details and conform to existing APIs

Testing

• I have included test coverage for these changes, or explained why they are not needed
• All automated tests pass, or I explained why that is not possible
• I have personally tested this on my device, or explained why that is not possible

Final pass

• Code is as readable as possible.
• I have reviewed this PR myself, ensuring it meets each checklist item

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