docs: remove peer recovery planning artifact

[M4n5ter]

Summary

Remove docs/architecture/peer-reachability-recovery-plan.md. It was an internal implementation and review log that should not have been committed as durable repository documentation.

This changes no code or product behavior.

Verification

• git diff --check
• Confirmed the document has no repository references before removal.
• Code tests were not run because this PR only deletes an unreferenced planning artifact.

AI use

Select exactly one:

• No generative tool made a substantive contribution
• Generative tooling made a substantive contribution

Tool(s) and scope: Codex identified and removed the planning artifact and prepared this PR.

Checklist

• Tests cover the change and fail without it — not applicable to deleting an unreferenced planning artifact
• Lint, format, typecheck and the affected suites pass locally — code is unchanged; git diff --check passed

Does this PR entail a change in behavior?

• Yes — described under Summary above
• No

[jackwener]

Approved at exact head a06eaf575eb8816f0b2a1d116787c34224eed3c9 at the explicit direction of M4n5ter. No technical review was performed as part of this action; M4n5ter requested the approval and accepts responsibility for subsequent handling.

---

Review notice: This approval was submitted by an automated review agent operated by WAWQAQ and is published at the direction of M4n5ter, who requested this action and is the human accountable for it.