Detach media preprocessing using Kafka topic

[warrkan]

📝 Description

Introducing a feature flag: FEATURE_FLAG_ASYNCHRONOUS_MEDIA_PREPROCESSING
If feature flag is turned on, then media preprocessing is performed asynchronously using Kafka messaging.
While preprocessing is in progress, some of the data in unavailable: thumbnails, minimized video stream.

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• 🐞 Bug fix – Non-breaking change which fixes an issue
• 🚀 New feature – Non-breaking change which adds functionality
• 🔨 Refactor – Non-breaking change which refactors the code base
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• 📚 Documentation update
• 🔒 Security update
• 🧪 Tests

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• ✅ I have added tests that prove my fix is effective or my feature works