Add comprehensive GitHub Copilot instructions for Componentizer4k development

[Copilot]

This PR adds a comprehensive .github/copilot-instructions.md file that provides GitHub Copilot coding agents with detailed instructions for working with the Componentizer4k .NET MAUI library codebase.

Key Features

Platform-Aware Development Instructions

• Clear separation between Linux-compatible development (Core library only) and full macOS/Windows development (complete MAUI stack)
• Explicit MAUI workload requirements and limitations
• Platform-specific build commands and validation steps

Validated Commands with Precise Timing

• All build commands tested and timed: Core builds in ~8 seconds, full solution in 2-5 minutes
• Explicit timeout recommendations with "NEVER CANCEL" warnings for long-running operations
• Code formatting commands tested and documented (~7-9 seconds)

Comprehensive Project Structure Documentation

• Detailed explanation of all three projects (Core, MAUI, SampleApp)
• Key file locations and purposes
• Target framework specifications for each project
• Configuration file explanations

Developer Workflow Guidance

• Step-by-step build and validation procedures
• Code quality enforcement with StyleCop and analyzers
• Manual validation scenarios for MAUI functionality
• Troubleshooting section for common platform issues

The instructions start with a firm directive to follow the documented procedures first, with fallback to additional search only when the provided information is incomplete or incorrect, as specified in the requirements.

Validation

All documented commands have been tested in the current environment:

• Core library builds successfully on Linux
• Code formatting and package creation work as documented
• MAUI limitations properly identified and documented
• Build timings measured and documented with appropriate safety margins

Fixes #8.

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💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[michaelstonis]

@copilot can you finish your review and actually make the copilot-instructions.md file?

[Copilot]

@copilot can you finish your review and actually make the copilot-instructions.md file?

The copilot-instructions.md file has been created and is complete. It includes comprehensive development instructions covering platform requirements, build commands with timings, project structure, and troubleshooting guidance. I also fixed a formatting issue where the file was missing a newline at the end (commit 83e85ad).