chore: add kafka type in oss

[Sarthak160]

Describe the changes that are made

This pull request adds support for Kafka as a new integration and mock type throughout the codebase. The changes introduce a new KafkaSchema struct, update the mock specification to include Kafka request and response payloads, and extend the YAML encode/decode logic to handle Kafka mocks.

Kafka integration and mock support:

• Added KAFKA as a new IntegrationType in integrations.go and as a new Kind in mock.go, enabling Kafka as a recognized integration and mock type. [1] [2]
• Extended the MockSpec struct to include KafkaRequests and KafkaResponses fields, allowing mocks to store Kafka-specific payloads.
• Introduced a new KafkaSchema struct in models/redis.go to define the schema for Kafka mocks, including metadata, request/response bins, and timestamp fields.

YAML encode/decode enhancements:

• Updated the EncodeMock function to handle Kafka mocks by marshaling the new KafkaSchema into YAML, with appropriate error handling and logging.
• Updated the DecodeMocks function to decode Kafka mocks from YAML into the new KafkaSchema and populate the MockSpec accordingly.

Links & References

Closes: #[issue number that will be closed through this PR]

• NA (if very small change like typo, linting, etc.)

🔗 Related PRs

• NA

🐞 Related Issues

• NA

📄 Related Documents

• NA

What type of PR is this? (check all applicable)

• 📦 Chore
• 🍕 Feature
• 🐞 Bug Fix
• 📝 Documentation Update
• 🎨 Style
• 🧑‍💻 Code Refactor
• 🔥 Performance Improvements
• ✅ Test
• 🔁 CI
• ⏩ Revert

Added e2e test pipeline?

• 👍 yes
• 🙅 no, because they aren't needed
• 🙋 no, because I need help

Added comments for hard-to-understand areas?

• 👍 yes
• 🙅 no, because the code is self-explanatory

Added to documentation?

• 📜 README.md
• 📓 Wiki
• 🙅 no documentation needed

Are there any sample code or steps to test the changes?

• 👍 yes, mentioned below
• 🙅 no, because it is not needed

Self Review done?

• ✅ yes
• ❌ no, because I need help

Any relevant screenshots, recordings or logs?

• NA

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