Add captured configuration comparison

configuration_inspection.go

@@ -27,6 +27,20 @@ func (e *Engine) InspectConfiguration() (ConfigurationInspection, error) {
 	return ConfigurationInspection{source: e.internal.InspectConfiguration()}, nil
 }
 
+// Diff compares this view's captured effective configuration with other. This
+// view is the earlier (left) value and other is the later (right) value. The
+// comparison delegates to ConfigKit's frozen effective-value semantics, so
+// source or resolution history alone does not create differences. Either zero
+// view returns ErrInvalidConfig and no records. Returned records can contain
+// ordinary application data and are not evidence of equivalent execution
+// behavior; callers choose where and to whom to disclose them.
+func (v ConfigurationInspection) Diff(other ConfigurationInspection) ([]configkit.Difference, error) {
+	if v.source == nil || other.source == nil {
+		return nil, ErrInvalidConfig
+	}
+	return configuration.Diff(v.source, other.source)
+}
+
 // Metadata returns detached effective presence and history records.
 func (v ConfigurationInspection) Metadata() configkit.Metadata {
 	if v.source == nil {