Skills with `metadata` as last frontmatter field are not discovered

[kamja-bq]

Describe the bug

Skills are not discovered when the metadata field (nested YAML) is the last field in SKILL.md frontmatter.

VS Code Copilot Chat does NOT have this issue - it correctly discovers skills regardless of field order. This bug is specific to Copilot CLI.

Affected version

0.0.380 Commit: 39ff7b7

Steps to reproduce the behavior

1. Create a skill at ~/.copilot/skills/sample-skill/SKILL.md with this content:

name: sample-skill
description: A sample skill for testing.
metadata:
  author: test

Sample Skill

2. Run copilot in terminal
3. Observe "No skills found" or skill missing from /skills list
4. Add any field after metadata (e.g., license: MIT)
5. Restart copilot - skill is now discovered

Expected behavior

Skills should be discovered regardless of field order in frontmatter, as long as the YAML is valid per the Agent Skills specification (https://agentskills.io/specification).

This is the current behavior in VS Code Copilot Chat, which handles these skills correctly.

Additional context

• Operating system: Windows 11
• CPU architecture: x86_64
• Terminal emulator: Windows Terminal / VS Code integrated terminal
• Shell: PowerShell

Workaround: Add any simple field (e.g., license: MIT or compatibility: ...) after the metadata block.

Working example:

name: sample-skill
description: A sample skill for testing.
metadata:
  author: test
license: MIT

The Agent Skills specification (https://agentskills.io/specification) shows an example with metadata as the last field, confirming this is valid YAML frontmatter. No field ordering is specified or required.