Support global ~/.agents/skills by default (user scope)

Variant

CLI

Feature

Please load ~/.agents/skills by default as a user/global scope (similar to current ~/.codex/skills), so skills can be shared across repos without symlinks. Repo .agents/skills is great, but it only covers relative paths.

Additional information

• PR #10317 adds support for repo .agents/skills (CWD → project root), but it doesn’t cover a global ~/.agents/skills location.
• This would be a natural replacement for ~/.codex/skills as it’s being deprecated.
• Suggested search order: repo .agents/skills (CWD → root), then user ~/.agents/skills (or make it configurable, e.g. skills.user_dir).
• Environment: codex-cli 0.94.0, macOS Tahoe 26.2.