Add Dependabot auto-merge workflow

[Marenz]

Summary

• Add GitHub workflow to automatically approve and merge Dependabot PRs
• Uses merge method for clean commit history

[Copilot]

Pull Request Overview

Adds a GitHub Actions workflow to automatically approve and merge Dependabot pull requests using a merge commit for clean history.

• Introduces a new workflow file auto-dependabot.yaml.
• Configures a job gated by actor check for dependabot[bot].
• Uses a third-party action to auto-approve and merge PRs with merge-method set to merge.

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[Copilot]

The workflow relies on GITHUB_TOKEN to approve and merge, but no explicit permissions block is set; GitHub defaults may be read-only and cause the action to fail. Add a top-level permissions section: permissions: contents: write, pull-requests: write to ensure the action can approve and merge.

[Copilot]

[nitpick] This configuration will auto-merge every Dependabot PR regardless of update type (major/minor/patch), which can introduce breaking changes automatically. Consider adding logic (e.g., fetch metadata action + conditional) to restrict merges to patch/minor versions only.

[Copilot]

[nitpick] Triggering on all pull_request event types can create unnecessary workflow runs; specify types (e.g., types: [opened, synchronize, reopened]) to reduce redundant executions.

Suggested change

	types: [opened, synchronize, reopened]

[llucax]

Nitpick.

[llucax]

Missing EOL.