Cross-provider subagents

[FYZAFH]

This is just a discussion, not a requirement submission. I believe GPT or Gemini have better mathematical and logical capabilities and longer context (their training tendencies differ slightly from Claude's), and outsourcing this part may save the main agent's context length. Additionally, Claude is indeed somewhat too expensive. Would it be better to package some relatively independent tasks and hand them over to Codex? My concern is whether this would disrupt the existing workflow (especially debugging and fixing, which is more tightly coupled with superpower than code review)?