--add-dir does not load skills from added directory when running Copilot CLI outside that directory #3173

Describe the bug

When running Copilot CLI from a different directory and using copilot --add-dir <path>\add-dir-test, Copilot CLI does not load skills that exist inside the added directory.

The issue happens even when the added directory contains valid skill definitions under all supported skill locations.

Affected version

GitHub Copilot CLI 1.0.43.

Steps to reproduce the behavior

1. Create the following directory structure:

add-dir-test
├─.agents
│  └─skills
│      └─my-skill
│              SKILL.md
│
├─.claude
│  └─skills
│      └─my-skill
│              SKILL.md
│
├─.copilot
│  └─skills
│      └─my-skill
│              SKILL.md
│
└─.github
    └─skills
        └─my-skill
                SKILL.md

2. Put the following content in each SKILL.md:

---
name: my-skill
description: A brief description of what my skill does.
---

# My Skill

3. Open a terminal in a directory other than add-dir-test.
4. Run:

copilot --add-dir <path>\add-dir-test

5. Check whether Copilot CLI discovers and loads the skills inside the added directory.

Expected behavior

Copilot CLI should discover and load skills from the directory passed to --add-dir, including skills located under:

• .agents\skills\my-skill\SKILL.md
• .copilot\skills\my-skill\SKILL.md
• .github\skills\my-skill\SKILL.md

Additional context

• OS: Windows
• The issue occurs when Copilot CLI is started outside add-dir-test and the directory is added via --add-dir
• The skills are present and structured correctly, but they are not loaded from the added directory