Cover cxxreact:tracesection with Stable API guards (#58400)

Summary:
Pull Request resolved: #58400

Classifies `cxxreact:tracesection` as a "for frameworks" target under the three-tier C++ stable API visibility model. Consumers that opt into `RN_STRICT_API` now get a warning if they include its headers directly, which they can acknowledge with `RN_ALLOW_FRAMEWORKS`; without that flag the guards are inert, so no existing build changes behaviour.

Changelog: [Internal]

Differential Revision: D119163904

Author: j-piasecki

packages/react-native/ReactCommon/cxxreact/ReactMarker.h

@@ -7,6 +7,8 @@
 
 #pragma once
 
+#include <react/cxxstableapi/FrameworksGuard.h>
+
 #include <cmath>
 #include <functional>
 #include <mutex>

packages/react-native/ReactCommon/cxxreact/SystraceSection.h

@@ -7,6 +7,8 @@
 
 #pragma once
 
+#include <react/cxxstableapi/FrameworksGuard.h>
+
 #include "TraceSection.h"
 
 // NOTE: This is here for a backwards compatibility and should be removed once

packages/react-native/ReactCommon/cxxreact/TraceSection.h

@@ -7,6 +7,8 @@
 
 #pragma once
 
+#include <react/cxxstableapi/FrameworksGuard.h>
+
 #ifdef WITH_FBSYSTRACE
 #include <fbsystrace.h>
 #endif