Add GitHub Actions workflow for documentation deployment

[ncipollina]

🚀 Pull Request

📋 Summary

Briefly describe what this PR does and why it's needed.

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✅ Checklist

• My changes build cleanly
• I’ve added/updated relevant tests
• I’ve added/updated documentation or README
• I’ve followed the coding style for this project
• I’ve tested the changes locally (if applicable)

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🧪 Related Issues or PRs

Closes #...

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💬 Notes for Reviewers

Any specific areas to look at, known issues, or follow-up work.

[Copilot]

Pull Request Overview

This PR updates the GitHub Actions workflow for documentation deployment by replacing the existing MkDocs workflow with a new, more comprehensive version. The new workflow includes improved dependency management, caching, and conditional deployment logic.

Key changes:

• Replaces the old mkdocs-material-gh-pages.yml with a new docs.yml workflow
• Adds pull request triggers for documentation validation
• Implements dependency caching and conditional deployment to production

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
LayeredCraft.Cdk.Constructs.sln	Updates solution file reference to point to the new workflow filename
.github/workflows/mkdocs-material-gh-pages.yml	Removes the old documentation deployment workflow
.github/workflows/docs.yml	Adds new documentation workflow with enhanced features including PR validation, caching, and conditional deployment

[ncipollina]

@all-contributors please add @ncipollina for code, doc, and infrastructure

[allcontributors]

@ncipollina

I've put up a pull request to add @ncipollina! 🎉