Skill discovery from priv, project, and user directories.
Summary
Functions
@spec apis(keyword()) :: [Vibe.Plugin.API.t()]
@spec discover(keyword()) :: [Vibe.Skill.Executable.t()]
@spec load_dir(String.t()) :: {:ok, [Vibe.Skill.Executable.t()]} | {:error, term()}
@spec load_file(String.t()) :: {:ok, [Vibe.Skill.Executable.t()]} | {:error, term()}