structural_error

pub struct StructuralError {
    pub path: String,
    pub code: StructuralErrorCode,
    pub message: String,
    pub details: Value,
}

type StructuralError struct {
	// Path is an RFC 6901 JSON Pointer to the offending component
	// ("/models/x/equations/0", "/reaction_systems/x/reactions/0/substrates/1/species"),
	// matching SchemaError.Path and the shared invalid-fixture goldens. The
	// document root is the empty string "".
	Path    string         `json:"path"`
	Code    string         `json:"code"`    // Machine-readable error code
	Message string         `json:"message"` // Human-readable description
	Details map[string]any `json:"details"` // Additional context
	// Level is "warning" for advisory findings that do NOT invalidate the
	// document (e.g. a species listed twice in a reaction), or "" / "error"
	// for hard errors. It is omitempty so hard errors keep their original wire
	// shape; only warnings carry an explicit level.
	Level string `json:"level,omitempty"`
}