ci: replace deployment action with builtin deployment support

[radoering]

We get the following warning in our actions:

Node.js 20 actions are deprecated. The following actions are running on Node.js 20 and may not work as expected: bobheadxi/deployments@648679e8e4915b27893bd7dbc35cb504dc915bc8.
Actions will be forced to run with Node.js 24 by default starting June 2nd, 2026. Node.js 20 will be removed from the runner on September 16th, 2026.
Please check if updated versions of these actions are available that support Node.js 24. To opt into Node.js 24 now, set the FORCE_JAVASCRIPT_ACTIONS_TO_NODE24=true environment variable on the runner or in your workflow file. Once Node.js 24 becomes the default, you can temporarily opt out by setting ACTIONS_ALLOW_USE_UNSECURE_NODE_VERSION=true.
For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

bobheadxi/deployments may be unmaintained:

• last commit two years ago
• Interest in contributing as maintainer bobheadxi/deployments#169

However, we probably do not even need a custom action but can just rely on github's builtin deployment mechanism.

[github-actions]

Deploy preview for website ready!

Project:	website
Status:	✅  Deploy successful!
Preview URL:	https://website-4mw4l5sso-python-poetry.vercel.app
Latest Commit:	0c97961

Deployed with vercel-action

[Copilot]

Pull request overview

Updates the GitHub Actions deployment workflows to stop using the bobheadxi/deployments action (flagged for Node.js 20 deprecation / likely unmaintained) and instead use GitHub’s built-in Environment deployment tracking by attaching environment metadata to the deployment jobs.

Changes:

• Add environment.name and environment.url to Preview and Production deployment jobs.
• Remove bobheadxi/deployments start/finish steps and the associated deployments: write permission.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
.github/workflows/deploy-production.yaml	Switches production workflow from custom deployments action to GitHub Environment metadata (name + URL), removing deployments action steps/permissions.
.github/workflows/deploy-preview.yaml	Switches preview workflow from custom deployments action to GitHub Environment metadata (name + URL), removing deployments action steps/permissions.

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