Improve nest camera stream expiration to be defensive against errors

[allenporter]

Proposed change

Harden nest stream expiration by adding backoff and ensuring that failures are handled defensively to avoid immediately retrying. This also adds a defense against a bad clock that could result in an immediate retry by setting a minimum interval.

The retry logic is extracted to a helper class, and now each WebRTC stream has its own alarm rather than a single alarm that refreshes all streams. This is needed to make the logic for managing backoff or the min refresh interval simpler since it only has to consider one stream at a time.

Adds a test that exercises a case where a refreshed stream expires in the past and ensuring it waits a minimum refresh period before extending the stream.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes Nest Cameras/Doorbell showing too many API calls since latest HA update #130061
• This PR is related to issue:
• Link to documentation pull request:

Checklist

• The code change is tested and works locally.
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• Tests have been added to verify that the new code works.

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