Add multithreaded logging infrastructure for preparation for future designs (#225)

* Update class diagrams

* Implement BoundedChannel and multithreaded logging infra

* Integrate logging channel system

* Update string concatenations to use std::format

* Add pretty print log

tooling/pipeline/includes/services/logging/logger.h

@@ -0,0 +1,64 @@
+/**
+ * @file services/logging/logger.h
+ * @brief Abstract logging interface used by pipeline components.
+ *
+ * The interface keeps application code independent from the concrete logging
+ * transport, buffering, and formatting implementation.
+ */
+
+#ifndef BIERGARTEN_PIPELINE_INCLUDES_SERVICES_LOGGING_LOGGER_H_
+#define BIERGARTEN_PIPELINE_INCLUDES_SERVICES_LOGGING_LOGGER_H_
+
+#include <source_location>
+#include <string>
+#include <utility>
+
+#include "services/logging/log_entry.h"
+
+/**
+ * @class ILogger
+ * @brief Minimal interface for submitting structured log messages.
+ *
+ * Implementations are non-copyable and non-movable. They are typically owned
+ * by the composition root and injected into services that emit diagnostics.
+ */
+class ILogger {
+ public:
+  ILogger() = default;
+  ILogger(const ILogger&) = delete;
+  ILogger& operator=(const ILogger&) = delete;
+  ILogger(ILogger&&) = delete;
+  ILogger& operator=(ILogger&&) = delete;
+  virtual ~ILogger() = default;
+
+  /**
+   * @brief Submit a log message to the logging subsystem.
+   *
+   * @param payload User-provided log data (level, phase, message).
+   * @param origin Auto-captured source location of the call site.
+   */
+  void Log(LogDTO payload,
+           std::source_location origin = std::source_location::current(),
+           std::chrono::system_clock::time_point timestamp = std::chrono::system_clock::now(),
+           std::thread::id thread_id = std::this_thread::get_id()) {
+    LogEntry entry;
+    entry.timestamp = timestamp;
+    entry.thread_id = thread_id;
+    entry.level = payload.level;
+    entry.phase = payload.phase;
+    entry.message = std::move(payload.message);
+    entry.origin = origin;
+    DoLog(std::move(entry));
+  }
+
+ protected:
+  /**
+   * @brief Underlying implementation to transport the log entry.
+   *
+   * Implementations must be thread-safe as DoLog can be called concurrently
+   * from multiple worker threads.
+   */
+  virtual void DoLog(LogEntry log_entry) = 0;
+};
+
+#endif  // BIERGARTEN_PIPELINE_INCLUDES_SERVICES_LOGGING_LOGGER_H_