Devex: Automerge Weblate PRs with the merge strategy

[tristanlabelle]

Weblate PRs must be merged using the merge strategy, otherwise we later run into Weblate merge conflicts. We can configure the merge strategy by setting automerge. This will still require a human approval due to branch protection rules.

Testing

None: New github workflows are generally not testable, especially if they target PRs to develop. I'll have to wait until the next time Weblate opens a PR.

For maintainers

• Maintainers can push commits to my branch
• Maintainers can merge this PR for me

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Project	Deployment	Actions	Updated (UTC)
couchers	Ready	Preview	May 8, 2026 7:30am

[github-actions]

📝 Release Notes

This PR does not need to be included in release notes.

Reason: This PR only adds a GitHub workflow to automatically set Weblate translation PRs to use a specific merge strategy. It is a developer workflow/internal maintenance change and does not create a noticeable end-user feature or significant user-facing reliability improvement on the platform itself.

🤖 Bot Debug Information

Model: couchers.openai.gpt-5.4
Decision: exclude
Reasoning: This PR only adds a GitHub workflow to automatically set Weblate translation PRs to use a specific merge strategy. It is a developer workflow/internal maintenance change and does not create a noticeable end-user feature or significant user-facing reliability improvement on the platform itself.