cks-runtime v1.58.0 – add dead-letter retry storage capability

Added

• Dead-letter task retry/requeue – new retry_dead_letter_task(task_id: str) -> bool method on runtime storage interfaces and implementations.
• Implemented for SQLiteStorage and PostgresStorage; no-op/False for unsupported backends such as InMemoryStorage.
• Requeue moves a DEAD outbox task back to PENDING and resets claimed_at, last_error, and retry/lease state while preserving task_type, payload, and session_id.
• Added conformance tests for successful requeue, missing/non-DEAD tasks, re-claim after requeue, and unsupported backend no-op behavior.

Changed

• RuntimeStorage and AsyncRuntimeStorage now declare retry_dead_letter_task.
• SyncStorageAdapter forwards retry_dead_letter_task to the wrapped sync storage.

Notes

• No breaking changes to existing storage methods or public behavior.