Function validate_canonical_sequence_diagnostic 

pub fn validate_canonical_sequence_diagnostic<N: Network>(
    state: &CanonicalSequenceState,
    batch: &ReactiveInputBatch<N>,
) -> Result<CanonicalSequenceValidation, CanonicalSequenceError>

Validate one provider-neutral delivery envelope and retain structured rollback diagnostics.

This is the diagnostic counterpart to validate_canonical_sequence. Use it at durable/composite source boundaries that need to distinguish malformed input from an otherwise valid transition whose rollback ancestor has aged out of the retained history. Callers should branch on CanonicalSequenceError rather than parsing error text.

Errors

Returns CanonicalSequenceError::Invalid for malformed or contradictory state/input and CanonicalSequenceError::IncompleteRollback when more retained canonical history is required to prove the transition.