Add eventing layer research report

[dgee2]

This checks the existing eventing-layer research into the repository so reviewers and future contributors can find it alongside the codebase instead of only in chat session storage.

Summary

• add the existing markdown research report under the top-level research/ directory
• keep the change scoped to repository documentation only, with no application code updates

[Copilot]

Pull request overview

Adds a markdown research report documenting evaluation of eventing-layer options (libraries and transports) for the Menu backend, with recommendations centered on MassTransit + RabbitMQ + transactional outbox. Pure documentation; no code changes.

Changes:

• Add new research document under research/
• Document scoring rubric, options, and recommendations
• Include Windows-style absolute path citations to backend source files

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[dgee2]

🤖 This comment was written by GitHub Copilot.

Regarding the SonarQube status comment, this appears to be informational only, so I’m declining it. SonarQube reports a passing Quality Gate with no new issues, and this PR only adds a research Markdown file, so no code or test change is needed.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud