fix: Docker run port mapping mismatch in release workflow documentation

[coderabbitai]

Description

The docker run command in .github/workflows/release.yml maps container port 80, but the Dockerfile now uses nginxinc/nginx-unprivileged:alpine which exposes port 8080. Users following the published release instructions will get a connection refused error.

Steps to reproduce

1. Follow the Docker instructions published in a GitHub Release.
2. Run: docker run -p 7777:80 ghcr.io/<repo>:<version>
3. Attempt to access http://localhost:7777 — connection will be refused.

Expected fix

Update the port mapping in the release workflow body:

-            docker run -p 7777:80 ghcr.io/${{ github.repository }}:${{ steps.tag.outputs.VERSION }}
+            docker run -p 7777:8080 ghcr.io/${{ github.repository }}:${{ steps.tag.outputs.VERSION }}

References

• PR: feat: receive payments directly without Lightning Address #61
• Review comment: feat: receive payments directly without Lightning Address #61 (comment)

Requested by: @Delgado74