Feature Request: Support global ~/.agents/AGENTS.md along with project-level AGENTS.md

Claude Code currently supports global configurations under ~/.claude/CLAUDE.md and local rules in CLAUDE.md. However, to prevent cross-tool duplicate prompting when developers use multiple CLI agents (e.g. Claude Code, Qwen, Codex, Goose, Kilo), we need support for the global unified standard:
~/.agents/AGENTS.md

Proposed Behavior

• If ~/.agents/AGENTS.md is present in the user's home directory, load it as global developer instructions.
• This allows developers to maintain their security rules, OODA reasoning guidelines, and operational frameworks in one place, sharing them seamlessly across Claude Code and other terminal tools.