Add Github Copilot setup steps for SQL Server

[roji]

This adds a first version of copilot-setup-steps.yml to the repo, to properly set up the environment in which Github Copilot agent sessions execute; it notably starts up a SQL Server 2025 inside docker. This first PR only inserts a first version, I'll be iterating over this in subsequent PRs (once the workflow is checked into main, it's easier to iterate).

See https://docs.github.com/en/copilot/how-tos/use-copilot-agents/coding-agent/customize-the-agent-environment

[SamMonoRT]

What is the impact on existing CI infrastructure - as in longer run times, or is this purely only when using GH Copilot?

[roji]

Purely only when using GH Copilot.

[Copilot]

Pull request overview

This PR adds a GitHub Actions workflow file (copilot-setup-steps.yml) to configure the environment for GitHub Copilot agent sessions, including starting a SQL Server 2025 instance in Docker. The PR also reorganizes the solution file to better organize GitHub-related files into appropriate folders.

Changes:

• Added .github/workflows/copilot-setup-steps.yml workflow to start SQL Server 2025 in Docker and configure the environment for Copilot agent sessions
• Reorganized EFCore.slnx to group GitHub-related files into .github/ and .github/workflows/ folders

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
.github/workflows/copilot-setup-steps.yml	New workflow that starts SQL Server 2025 via Docker service, runs restore script, and exports connection string environment variable
EFCore.slnx	Reorganized solution structure to group GitHub workflow files into dedicated folders

[SamMonoRT]

Do we need any changes in https://github.com/dotnet/efcore/blob/main/.github/copilot-instructions.md ?

[roji]

Do we need any changes in https://github.com/dotnet/efcore/blob/main/.github/copilot-instructions.md ?

Yeah, we most probably will - but I want to iterate this in a separate PR (first want to see this actually working etc.).

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.