Add comprehensive copilot-instructions.md for Windows Driver Docs DDI repository

[Copilot]

This PR adds a comprehensive copilot-instructions.md file to help developers using GitHub Copilot contribute effectively to the Windows Driver Docs DDI repository.

Overview

The new instructions file provides detailed guidance for working with the 25,800+ documentation files in this repository, which document Windows Driver Kit (WDK) Device Driver Interface (DDI) APIs published at learn.microsoft.com/windows-hardware/drivers/ddi.

Key Features

File Naming Convention Reference

Includes a comprehensive table documenting the filename prefixes used throughout the repository:

• ne- for enumerations (2,505 files)
• nc- for callback functions (3,126 files)
• ni- for IOCTL codes (800 files)
• ns- for structures (7,513 files)
• nl- for C++ classes (20 files)
• nn- for COM interfaces (470 files)
• nf- for functions (10,882 files)

AI Usage Guidelines

Provides clear requirements for the ai-usage metadata attribute that must be included when AI is used to create or revise content:

• ai-assisted: Content created by human with AI help
• ai-generated: Content created by AI with human review

This metadata automatically adds customer-facing AI disclosure to published content.

Link Format Standards

Establishes the requirement to use site-relative links instead of fully qualified URLs:

• ✅ Correct: /windows-hardware/drivers/ddi/ntifs/nf-ntifs-ccpreparemdlwrite
• ❌ Wrong: learn.microsoft.com/windows-hardware/drivers/ddi/ntifs/nf-ntifs-ccpreparemdlwrite

Content Structure Guidance

Documents the standard YAML frontmatter requirements and content sections including:

• Required metadata fields (UID, title, description, tech.root)
• API documentation patterns for functions, structures, enums, etc.
• Cross-referencing standards and see-also sections

Repository-Specific Best Practices

Provides practical guidance for maintaining consistency across the large codebase, including technology area classifications, metadata validation, and contribution workflows.

Impact

This documentation will help ensure that AI-assisted contributions to the Windows Driver documentation maintain the high quality and consistency standards required for official Microsoft technical documentation while properly attributing AI usage to readers.

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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.