Add GitHub Copilot instructions for FLAML repository

[Copilot]

Configures repository-wide Copilot coding agent instructions following GitHub best practices.

Changes

• Created .github/copilot-instructions.md containing:
  • Project structure and key components (automl, tune, default, fabric)
  • Build/test/lint commands with exact flags used in CI
  • Code style rules (Black 120 char, Ruff with pycodestyle/pyflakes)
  • Python version support matrix (3.10-3.12 fully supported, 3.13 in CI)
  • Testing requirements (multi-version, multi-platform, pytest markers)
  • Dependency constraints and optional feature groups
  • Explicit boundaries (do not modify: LICENSE, .git/, version.py)
  • AutoGen migration context (moved to separate repo)
  • Security and platform-specific considerations

The instructions enable Copilot agents to understand project conventions, testing requirements, and constraints without additional context.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• gh.io
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node /home/REDACTED/work/_temp/ghcca-node/node/bin/node --enable-source-maps /home/REDACTED/work/_temp/copilot-developer-action-main/dist/index.js (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>✨ Set up Copilot instructions</issue_title>
<issue_description>Configure instructions for this repository as documented in Best practices for Copilot coding agent in your repository.

Don't forget to run pre-commit run --all-files to fix format issues.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes ✨ Set up Copilot instructions #1501

---

💡 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.