[AND-21 ]Expose Closed Captionss Start and Stop Rest Apis, Add WS Events for Closed Captions

[rahul-lohra]

1. Expose CC start and stop Rest Api
2. Create its response model
3. Create WS events and map it
4. Add CaptionManager to handle closed caption related properties

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🛠 Implementation details

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🎨 UI Changes

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☑️Reviewer Checklist

• XML sample runs & works
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