docs(other): add blog post introducing the Replay tab in Reunite

[vital4u4ok]

What/Why/How?

• Added a new blog post introducing the Replay tab in Reunite, written for existing Reunite users adopting the feature.

Reference

• Internal: feature is documented at https://redocly.com/docs/realm/reunite/project/test-api-functions.

Testing

Screenshots (optional)

Check yourself

• Code is linted
• Tested
• All new/updated code is covered with tests

Security

• Security impact of change has been considered
• Code follows company security practices and guidelines

[redocly]

marketing-site AI Review: 🟢 Completed

Reunite Agent has reviewed your changes and found 7 potential issue(s).

Note

Low Risk

This PR only introduces documentation updates via a new blog post and its associated metadata/images. There are no functional code changes.

Overview

Adds a new blog post introducing the "Replay" tab in Reunite, a feature that allows users to test API functions directly inside the editor without switching to an external tool. Additionally, updates the blog-metadata.yaml file to register a new author (vitalii-skulskyi) and includes relevant screenshot images for the post.