Add pack runtime profiling hooks

src/PackLib/PackProfile.h

@@ -0,0 +1,29 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <string_view>
+
+void InitializePackProfile(const char* commandLine);
+bool IsPackProfileEnabled();
+void MarkPackProfilePhase(std::string_view phase);
+void RecordPackProfileMount(
+	std::string_view format,
+	std::string_view packPath,
+	bool ok,
+	std::size_t entryCount,
+	std::uint64_t elapsedUs);
+void RecordPackProfileLoad(
+	std::string_view format,
+	std::string_view packPath,
+	std::string_view requestPath,
+	bool ok,
+	std::uint64_t outputBytes,
+	std::uint64_t elapsedUs);
+void RecordPackProfileStage(
+	std::string_view format,
+	std::string_view stage,
+	std::uint64_t inputBytes,
+	std::uint64_t outputBytes,
+	std::uint64_t elapsedUs);
+void FlushPackProfileSnapshot(std::string_view reason);