Make TextInput descriptors and prop conversion helpers private

Summary:
Lower the following `react/renderer/components/textinput` headers from "for frameworks" to private:

Platform component descriptors:
- Android `androidtextinput/AndroidTextInputComponentDescriptor.h`
- iOS and macOS `iostextinput/TextInputComponentDescriptor.h`

All three classes are `final`, so they cannot be extended, and they are registered only by React Native's own platform glue (the Android core components registry and the iOS TextInput component view). The Android descriptor is additionally coupled to React Native's Java `FabricUIManager` (it reads theme padding over JNI in `getInitialState`).

Prop conversion helpers:
- `baseConversions.h` (conversions for the shared text input enums)
- iOS and macOS `iostextinput/propsConversions.h` (iOS/macOS text input trait parsers)

These are only included by the module's own props sources (`BaseTextInputProps.cpp` and the platform `TextInputProps.cpp` / `AndroidTextInputProps.cpp`).


Changelog: [Internal]

Differential Revision: D123643375

Author: coado

packages/react-native/ReactCommon/react/renderer/components/textinput/baseConversions.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <react/cxxstableapi/FrameworksGuard.h>
+#include <react/cxxstableapi/PrivateGuard.h>
 
 #include <React/RendererCore.h>
 #include <react/renderer/components/textinput/basePrimitives.h>

packages/react-native/ReactCommon/react/renderer/components/textinput/platform/android/react/renderer/components/androidtextinput/AndroidTextInputComponentDescriptor.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <react/cxxstableapi/FrameworksGuard.h>
+#include <react/cxxstableapi/PrivateGuard.h>
 
 #include "AndroidTextInputShadowNode.h"
 #include "AndroidTextInputState.h"

packages/react-native/ReactCommon/react/renderer/components/textinput/platform/ios/react/renderer/components/iostextinput/TextInputComponentDescriptor.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <react/cxxstableapi/FrameworksGuard.h>
+#include <react/cxxstableapi/PrivateGuard.h>
 
 #include <React/RendererCore.h>
 #include <react/renderer/components/iostextinput/TextInputShadowNode.h>

packages/react-native/ReactCommon/react/renderer/components/textinput/platform/ios/react/renderer/components/iostextinput/propsConversions.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <react/cxxstableapi/FrameworksGuard.h>
+#include <react/cxxstableapi/PrivateGuard.h>
 
 #include <React/Debug.h>
 #include <React/RendererCore.h>