Add Co-op Translator workflow

[skytin1004]

✨ Add Co-op Translator GitHub Action Workflow

This pull request introduces an automated translation workflow powered by Co-op Translator, which uses Azure AI and OpenAI to localize project content.

🚀 What This Workflow Does

Whenever changes are pushed to the main branch:

• It automatically translates updated content into multiple target languages
• Outputs translated markdown to the translations/ directory
• Outputs translated images (e.g., with localized text) to translated_images/
• Creates a pull request with the generated content using GitHub App authentication

🔧 Workflow Highlights

• Supports both Azure AI and OpenAI as backends
• Automatically reflects updates in:
  • URLs
  • Inline code
  • Sentence structure
• PRs are created using the peter-evans/create-pull-request action
• Temporary branches are deleted automatically (delete-branch: true)

ℹ️ Translation runs are triggered only when changes are pushed to main.
Translated files are regenerated, ensuring consistency with source content.

[github-actions]

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