Add TypeUtteranceEndResponse & handle case in live.router

[boyswan]

Proposed changes

Reference: #146

Types of changes

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
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Checklist

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• I have added tests that prove my fix is effective or that my feature works
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• Any dependent changes have been merged and published in downstream modules

[dvonthenen]

Thanks for the update. I'll take a look at this in a little bit! I super appreciate it!

[dvonthenen]

Hey @boyswan, these changes look great! Thanks a lot for your help on this! Really appreciate the contribution!