VS Code Custom Instructions for GitHub Copilot

VS Code Custom Instructions:

1. Create `.instructions.md` files in any directory
2. Instructions apply to Copilot Chat for files in that directory and subdirectories
3. Use front matter to specify file glob patterns
4. Combine with `.github/copilot-instructions.md` for layered context
5. Supports per-folder coding standards
6. Great for monorepos with different conventions per package

Example front matter:
```
---
applyTo: "**/*.tsx"
---
Use functional components with hooks. Prefer Tailwind CSS classes.
```

Tips:
- Keep instructions concise and actionable
- Use one file per distinct set of conventions
- Test instructions by asking Copilot Chat about conventions