fix(service): correct Convex origin env vars and expose HTTP actions port

[torstendngh]

Changes

The Convex one click service template assigns the origin env vars to the wrong services: CONVEX_CLOUD_ORIGIN points at the dashboard URL and CONVEX_SITE_ORIGIN points at the backend API URL. Convex generates file upload URLs from CONVEX_CLOUD_ORIGIN, so every upload gets POSTed to the dashboard and fails with a 404 ("Uploaded file appears to be HTML content" in the dashboard, "Failed to fetch" in apps). I hit this myself when my app's image upload broke after moving from Convex cloud to self-hosted on Coolify.

This PR points CONVEX_CLOUD_ORIGIN at the backend, declares SERVICE_URL_SITE_3211 so Coolify generates a second domain for the HTTP actions port (3211, previously unreachable), and points CONVEX_SITE_ORIGIN at that new domain. Three lines changed.

Issues

• Fixes [Bug]: Convex cannot store files locally or via S3 #7989
• Fixes [Bug]: Convex PUBLIC_CONVEX_SITE_URL is not exposed correctly #7232
• Same approach as Fix env variables in convex.yaml #7208, closed when Coolify could not generate URLs for two ports on one service. That works now.

Category

• Bug fix
• Fixing or updating existing one click service

AI Assistance

• AI was NOT used to create this PR
• AI was used (please describe below)

If AI was used:

• Tools used: Claude Code
• How extensively: Helped diagnose the root cause and draft this description, which I reviewed and edited. The change itself is three lines that I made and verified myself.

Testing

Deployed the modified compose on my own Coolify v4 instance (Hetzner VPS) running a Next.js + Convex app. Before the change, browser file uploads failed with a 404 because the upload URL pointed at the dashboard domain, matching the reports in #7989. After assigning a domain to the new SITE entry and redeploying: uploads work, stored files are servable, HTTP actions respond on the new domain, and the Convex CLI syncs the correct site URL into the env file.

Contributor Agreement

Important

• I have read and understood the contributor guidelines. If I have failed to follow any guideline, I understand that this PR may be closed without review.
• I have searched existing issues and pull requests (including closed ones) to ensure this isn't a duplicate.
• I have tested all the changes thoroughly with a local development instance of Coolify and I am confident that they will work as expected when a maintainer tests them.

[github-actions]

Hi @torstendngh! 👋

It appears to us that you are either adding a new service or making changes to an existing one.
We kindly ask you to also review and update the Coolify Documentation to include this new service or it's new configuration needs.
This will help ensure that our documentation remains accurate and up-to-date for all users.

Coolify Docs Repository: https://github.com/coollabsio/coolify-docs
How to Contribute a new Service to the Docs: https://coolify.io/docs/get-started/contribute/service#adding-a-new-service-template-to-the-coolify-documentation

[andrasbacsai]

Thank you for the PR! 💜