Connect HHT field convergence to production acceptance and v2 logs

include/fesa/analysis/newton_iteration_log.h

@@ -5,6 +5,7 @@
 #include <cstdint>
 #include <filesystem>
 #include <fstream>
+#include <optional>
 #include <string>
 
 #include "fesa/analysis/nonlinear_static_control.h"
@@ -52,6 +53,17 @@ struct NewtonIterationLogRecord {
   bool combined_passed;
 };
 
+/// @brief Vendor-neutral field evidence in full global u/total-phi coordinates.
+/// @note Missing quantities serialize as literal not-evaluated. Force uses
+/// force/length units; generalized moment uses moment/rad units.
+struct DynamicFieldLogEvidence {
+  std::optional<double> residual_numerator, residual_scale, spatial_flux;
+  std::optional<double> time_average_flux, correction_numerator, increment_norm;
+  std::optional<double> estimated_correction, residual_threshold, correction_threshold;
+  std::string branch = "not-evaluated";
+  std::optional<bool> residual_pass, correction_pass, field_pass;
+};
+
 /// @brief Carries two-channel HHT endpoint convergence evidence.
 /// @note Array entries are translation and rotation channels, respectively.
 /// Corrections are dimensionless N2 metrics; rate corrections already include
@@ -71,6 +83,14 @@ struct DynamicNewtonIterationLogRecord {
   std::array<double, 2U> algorithmic_correction{};
   bool residual_pass = false;
   bool correction_pass = false;
+  // Absent policy preserves the historical v1 direct-writer/frame-zero contract.
+  std::string policy_id;
+  std::string step_name;
+  std::array<DynamicFieldLogEvidence, 2U> fields;
+  std::optional<bool> field_pass;
+  bool accepted = false;
+  bool strict_residual_evaluated = false;
+  bool strict_correction_evaluated = false;
 };
 
 /// @brief Writes deterministic, line-oriented Newton iteration diagnostics.
@@ -90,7 +110,7 @@ class NewtonIterationLogWriter {
   /// failure with code `log-output-failure`.
   Status Write(const NewtonIterationLogRecord& record);
 
-  /// @brief Writes one complete HHT record using schema `hht-log-v1`.
+  /// @brief Writes HHT v1 evidence, or v2 when the field policy is identified.
   /// @return Success after the complete line is written; invalid numeric
   /// evidence or stream failure permanently fails this writer instance.
   Status Write(const DynamicNewtonIterationLogRecord& record);