chore: add copilot-instructions.md for the repo

[evalverde-vw]

📚 Description

Introduce a comprehensive copilot-instructions.md tailored for bashunit and our TDD-first workflow. It formalizes the ./tasks/ workflow (one file per change: YYYY-MM-DD-slug.md), enforces ADR reading/creation rules, and adds a label so DeepWiki can continuously scrape and keep the repository documentation up to date.

This PR is documentation/process-only; it makes no behavioral changes to the library itself.

🔖 Changes

• Add copilot-instructions.md at the repo root (English)

• Define strict TDD workflow and task files convention:

  • ./tasks/ with per-change files named YYYY-MM-DD-slug.md.
  • Keep .task/ as local working folder (ignored by Git) for any transient notes.

• Add .gitignore entries:

  • /.task/ → not versioned.

• Clarify ADR policy:

  • Read existing ADRs before changes.
  • When needed, create a new ADR using the template in /ADR/ and match existing ADR formatting.

• Include verified bashunit test examples (taken from actual repo patterns) in the instructions—no hypothetical snippets.

• Document Definition of Done: all tests green for the right reason, lint/format clean, docs updated.

• Add DeepWiki label/tag (e.g., deepwiki:track) to enable automated scraping/refresh of repository knowledge.

✅ To-do list

• I updated the CHANGELOG.md to reflect the new feature or fix
• I updated the documentation to reflect the changes

[antonio-gg-dev]

Do you know if Copilot supports agents.md? The idea would be to make it more compatible and not Copilot-specific. For example, I’ve been using GPT Codex lately, and it seems to me that agents.md is advocating for creating generalized instructions for all agents rather than specific ones for each.

(I find it more convenient if each developer can use the agent they prefer).

On https://agents.md/ page says that Copilot is compatible, but I’ don't know how to test it, I don’t have experience with Copilot. Could you try it?

[khru]

Do you know if Copilot supports agents.md? The idea would be to make it more compatible and not Copilot-specific. For example, I’ve been using GPT Codex lately, and it seems to me that agents.md is advocating for creating generalized instructions for all agents rather than specific ones for each.

(I find it more convenient if each developer can use the agent they prefer).

On https://agents.md/ page says that Copilot is compatible, but I’ don't know how to test it, I don’t have experience with Copilot. Could you try it?

What Copilot understands today

• Recognized by the Copilot Coding Agent (VS Code recent versions). Supported at the repo root and nested; the agent applies the closest file to where it’s operating.
• Repo instructions (copilot-instructions.md)
  A central file with rules/guidelines for the whole repo. Used by Copilot Chat, Code Review, and the Coding Agent.
• Path-scoped instructions (.github/instructions/*.instructions.md)
  Files with an applyTo (glob) to target folders/files. Honored by Copilot Chat in VS Code and the Coding Agent.

---

After looking a lot for it, this is what it supports. I generated it, but I can't test it @antonio-gg-dev can you test it and try it? and improve it if need it?

[antonio-gg-dev]

Working in Codex 👍🏻

[Chemaclass]

Thanks! Good from my side. Feel free to merge after the CI is green 🥳

[carlfriedrich]

@evalverde-vw Out of curiousity: does the ./tasks/ workflow originate from anywhere, or is this a bashunit-specific concept the team came up with themselves?

[carlfriedrich]

@evalverde-vw And another question: was the AGENTS.md file AI-generated or did you write that from scratch? How much time went into this?

[khru]

@evalverde-vw Out of curiousity: does the ./tasks/ workflow originate from anywhere, or is this a bashunit-specific concept the team came up with themselves?

@carlfriedrich it comes from my experience with LLM hallucination, so I started forcing them to have a "dump file" that forced them to keep the context, as well as a structure, that could help them in case the task needed to be re-worked.

@evalverde-vw And another question: was the AGENTS.md file AI-generated or did you write that from scratch? How much time went into this?

@carlfriedrich
Yes, it was created by sonet 4 following the copilot-instructions.md and it can be changed as you see fit.