fix: Repeated actionable challenges terminate payment handling early

[mpp-agricola]

Motivation

Agricola found that tempoxyz/pympp diverges from the canonical implementation: fix: Repeated actionable challenges terminate payment handling early

The Agricola ticket #169 contains the audit evidence, affected SDKs, and remediation lifecycle.

Summary

• Reconciles semantic:payment-retry/retry-repeated-actionable-challenges in the target SDK's idioms.
• Adds implementation and regression coverage for AGR-2026-058.
• Links the change to the Agricola ticket #169.

Key design considerations

• Limits scope to the audited delta between wevm/mppx@38d4cdc80301 and tempoxyz/pympp@9677facba7c2.
• Favors the target SDK's public API and conventions over a literal port.
• Uses the stable agricola/agr-2026-058 automation branch.
• Remains a draft until a maintainer reviews the generated changes.