[FEATURE] Add backend memory leak detection in CI

[ritik4ever]

Category: devops / performance / testing
Project area: .github/workflows/

Implementation:

• Run backend under load with clinic.js doctor.
• Fail CI if heap growth > 50MB over 5 minutes.
• Upload clinic report as artifact.

Acceptance Criteria:

• Baseline run passes.
• Injected leak detected.
• Report includes heap usage graph.

[utosjr1913]

@utosjr1913 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hello Maintainer, this looks like a great fit for my skills. I'd like to take this on and submit a solid PR.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @utosjr1913 to this issue.