Add AEM(adobe experience manager) front-end specialist agent mode

[aldunchev]

Pull Request Checklist

• I have read and followed the CONTRIBUTING.md guidelines.
• My contribution adds a new chat mode file in the correct directory.
• The file follows the required naming convention.
• The content is clearly structured and follows the example format.
• I have tested my instructions, prompt, or chat mode with GitHub Copilot.
• I have run npm start and verified that README.md is up to date.

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Description

This PR adds a comprehensive AEM (Adobe Experience Manager) Front-End Specialist chat mode designed for developers building production-ready AEM components using modern front-end technologies.

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Type of Contribution

• New chat mode file.

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Key Features:

• HTL (HTML Template Language)
• AEM Component Architecture and Core WCM Components
• Tailwind CSS v4 with custom design token systems
• BEM methodology for component structure
• Figma-to-code workflows using MCP Figma server
• Responsive design patterns (mobile-first)
• WCAG accessibility compliance
• Performance optimization strategies

This chat mode is particularly useful for teams working on AEM projects that need to maintain design system consistency, implement Figma designs accurately, and follow modern front-end best practices.

By submitting this pull request, I confirm that my contribution abides by the Code of Conduct and will be licensed under the MIT License.