Add persistent user preference recall across Codex CLI conversations

Hi @adrian.a.adewunmi Thanks for the clear write-up, the distinction you’re making between repo-level instructions (AGENTS.md) and user-level preferences across sessions is spot on. Right now Codex CLI is stateless, so things like commit style or PR structure need to be reintroduced or handled per-repo, which creates the friction you’re describing. The idea of separating repo conventions, user defaults, and per-chat overrides makes a lot of sense and fits well with real workflows. ~SD