Improve watchOS compatibility

[fhasse95]

This PR improves watchOS compatibility for this package.

It updates platform-specific code paths so they compile cleanly for watchOS while preserving the existing behavior.

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Skip Pull Request Checklist:

• REQUIRED: I have signed the Contributor Agreement
• REQUIRED: I have tested my change locally with swift test
• OPTIONAL: I have tested my change on an iOS simulator or device
• OPTIONAL: I have tested my change on an Android emulator or device

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• AI was used to generate or assist with generating this PR. Please specify below how you used AI to help you, and what steps you have taken to manually verify the changes.
  I used Codex to generate the initial version of the changes, then iteratively refined them myself and manually validated the behavior in my own watch app / extension.

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