[feat] Include debug symbols (dSYM) in the SDK

[nan-li]

Description

One Line Summary

Add debug symbols step to build script to include dSYM files in the SDK release.

Details

• Only the first 2 commits are relevant.
• The last 2 commits are for testing and will be removed after PR review.

Motivation

• On Xcode 16, SDK consumers were getting warnings about missing dSYMS. While app validation still succeeds, the warnings can be alarming or a nuisance. On previous Xcode versions, the warnings were not generated.
• This may also now help us symbolicate crash reports better

Scope

• Debug symbols only

Testing

Manual testing

How to Test
You can test using the steps under Testing the SDK in another app without release in our internal OneSignal-iOS-SDK Release Documentation.

• You can use this branch to add via Cocoapods
• SPM test branch is here: https://github.com/OneSignal/OneSignal-XCFramework/tree/dsym

I tested adding the SDK via both Cocoapods and Swift Package Manager. On both:

• app runs as expected
• the warnings went away

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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