chore: bump dependencies

[SelaseKay]

Description

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Related Issues

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Checklist

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• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• My PR includes unit or integration tests for all changed/updated/fixed behaviors (See Contributor Guide).
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Breaking Change

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[gemini-code-assist]

Code Review

This pull request updates the versions of several Firebase dependencies (such as firebase_auth, firebase_core, firebase_database, cloud_firestore, and firebase_storage) across multiple packages, examples, and tests. It also bumps the FirebaseFirestore pod version to 12.15.0 in the iOS and macOS Podfiles. There are no review comments to address, and I have no additional feedback to provide.