Update string concatenations to use std::format

add pretty print log

tooling/pipeline/includes/json_handling/pretty_print.h

@@ -0,0 +1,109 @@
+#ifndef BIERGARTEN_PIPELINE_INCLUDES_JSON_HANDLING_PRETTY_PRINT_H_
+#define BIERGARTEN_PIPELINE_INCLUDES_JSON_HANDLING_PRETTY_PRINT_H_
+
+/**
+ * @file json_handling/pretty_print.h
+ * @brief Pretty-printing utilities for JSON values.
+ *
+ * Provides formatting capability for boost::json::value with indentation and
+ * readable output. Adapted from Boost JSON library examples.
+ */
+
+#include <boost/json.hpp>
+#include <ostream>
+#include <string>
+
+/**
+ * @brief Pretty-prints a JSON value to an output stream with indentation.
+ *
+ * Recursively formats JSON objects and arrays with consistent 4-space
+ * indentation. Adapted from:
+ * https://raw.githubusercontent.com/boostorg/json/refs/heads/develop/example/pretty.cpp
+ *
+ * @param outstream Output stream to write formatted JSON.
+ * @param json_val JSON value to format.
+ * @param indent Optional indentation string (managed internally on first call).
+ */
+inline void PrettyPrint(std::ostream& outstream,
+                        boost::json::value const& json_val,
+                        std::string* indent = nullptr) {
+  std::string str;
+  if (indent == nullptr) {
+    indent = &str;
+  }
+  switch (json_val.kind()) {
+    case boost::json::kind::object: {
+      outstream << "{\n";
+      indent->append(4, ' ');
+      auto const& obj = json_val.get_object();
+      if (!obj.empty()) {
+        const auto* iter = obj.begin();
+        for (;;) {
+          outstream << *indent << boost::json::serialize(iter->key()) << " : ";
+          PrettyPrint(outstream, iter->value(), indent);
+          iter = std::next(iter);
+          if (iter == obj.end()) {
+            break;
+          }
+
+          outstream << ",\n";
+        }
+      }
+      outstream << "\n";
+      indent->resize(indent->size() - 4);
+      outstream << *indent << "}";
+      break;
+    }
+
+    case boost::json::kind::array: {
+      outstream << "[\n";
+      indent->append(4, ' ');
+      auto const& arr = json_val.get_array();
+      if (!arr.empty()) {
+        const auto* iter = arr.begin();
+        for (;;) {
+          outstream << *indent;
+          PrettyPrint(outstream, *iter, indent);
+          iter = std::next(iter);
+          if (iter == arr.end()) {
+            break;
+          }
+          outstream << ",\n";
+        }
+      }
+      outstream << "\n";
+      indent->resize(indent->size() - 4);
+      outstream << *indent << "]";
+      break;
+    }
+
+    case boost::json::kind::string: {
+      outstream << serialize(json_val.get_string());
+      break;
+    }
+
+    case boost::json::kind::uint64:
+    case boost::json::kind::int64:
+    case boost::json::kind::double_:
+      outstream << json_val;
+      break;
+
+    case boost::json::kind::bool_:
+      if (json_val.get_bool()) {
+        outstream << "true";
+      } else {
+        outstream << "false";
+      }
+      break;
+
+    case boost::json::kind::null:
+      outstream << "null";
+      break;
+  }
+
+  if (indent->empty()) {
+    outstream << "\n";
+  }
+}
+
+#endif