Remove Fabric and TurboModule dead config (#58434)

Summary:
Pull Request resolved: #58434

Follow-up to D116318829, addressing rubennorte's review comment. Fabric and TurboModules shipped before bridgeless and are always on, so the toggles for them were hardcoded and read nowhere.

Android, `DefaultNewArchitectureEntryPoint` — now only selects the release channel and loads the SO:
- removed `fabricEnabled`, `turboModulesEnabled`, `concurrentReactEnabled`
- removed the deprecated `load(turboModulesEnabled)` and `load(turboModulesEnabled, fabricEnabled)` overloads
- removed `isConfigurationValid`, and with it `DefaultNewArchitectureEntryPointTest` (every test targeted it)
- updated the 8 in-repo call sites that passed `fabricEnabled` into the deprecated 3-arg `DefaultReactActivityDelegate` constructor, which discarded it

iOS:
- removed `fabricEnabled` / `turboModuleEnabled` from `RCTRootViewFactoryConfiguration`
- removed the corresponding `RCTDefaultReactNativeFactoryDelegate` stubs and the `RCTAppDelegate.h` doc references

`ReactAndroid.api` and the `ReactApple*Cxx.api` snapshots are regenerated.

One call site is not updated here: `users/zh/zhaogang/benchmarks/SimpleRN/android/app/src/main/java/com/simplern/MainActivity.kt` still imports `DefaultNewArchitectureEntryPoint.fabricEnabled`. It is a personal benchmark app under `users/` that is not materialized in this working copy, so it could not be edited.

Changelog:
[General][Breaking] - Remove the `fabricEnabled` / `turboModulesEnabled` / `concurrentReactEnabled` accessors and remaining deprecated `load` overloads from `DefaultNewArchitectureEntryPoint`, and the `fabricEnabled` / `turboModuleEnabled` properties from `RCTRootViewFactoryConfiguration`; Fabric and TurboModules are always enabled

https://www.internalfb.com/agent-home?session_id=dmh-2bfbb113-43fc-4bc4-819d-874c5101a1c8

Reviewed By: javache

Differential Revision: D119380472

fbshipit-source-id: 19c130c3dda5c1cd6d541f4e726d8041b515c05c

Author: christophpurrer

packages/react-native/Libraries/AppDelegate/RCTAppDelegate.h

@@ -47,8 +47,6 @@ NS_ASSUME_NONNULL_BEGIN
  *   - (UIViewController *)createRootViewController;
  *   - (void)setRootView:(UIView *)rootView toRootViewController:(UIViewController *)rootViewController;
  * New Architecture:
- *   - (BOOL)turboModuleEnabled;
- *   - (BOOL)fabricEnabled;
  *   - (NSDictionary *)prepareInitialProps
  *   - (Class)getModuleClassFromName:(const char *)name
  *   - (std::shared_ptr<facebook::react::TurboModule>)getTurboModule:(const std::string &)name

packages/react-native/Libraries/AppDelegate/RCTDefaultReactNativeFactoryDelegate.mm

@@ -116,16 +116,6 @@ - (BOOL)newArchEnabled
   return YES;
 }
 
-- (BOOL)fabricEnabled
-{
-  return YES;
-}
-
-- (BOOL)turboModuleEnabled
-{
-  return YES;
-}
-
 - (Class)getModuleClassFromName:(const char *)name
 {
   return nullptr;

packages/react-native/Libraries/AppDelegate/RCTRootViewFactory.h

@@ -43,12 +43,6 @@ typedef void (^RCTLoadSourceForBridgeBlock)(RCTBridge *bridge, RCTSourceLoadBloc
 #pragma mark - RCTRootViewFactory Configuration
 @interface RCTRootViewFactoryConfiguration : NSObject
 
-/// This property controls whether the App will use the Fabric renderer of the New Architecture or not.
-@property (nonatomic, assign, readonly) BOOL fabricEnabled;
-
-/// This method controls whether the `turboModules` feature of the New Architecture is turned on or off
-@property (nonatomic, assign, readonly) BOOL turboModuleEnabled;
-
 /// Return the bundle URL for the main bundle.
 @property (nonatomic, nonnull) RCTBundleURLBlock bundleURLBlock;
 

packages/react-native/Libraries/AppDelegate/RCTRootViewFactory.mm

@@ -46,8 +46,6 @@ - (instancetype)initWithBundleURLBlock:(RCTBundleURLBlock)bundleURLBlock
 {
   if (self = [super init]) {
     _bundleURLBlock = bundleURLBlock;
-    _fabricEnabled = YES;
-    _turboModuleEnabled = YES;
   }
   return self;
 }

scripts/cxx-api/api-snapshots/ReactAppleDebugCxx.api

@@ -1693,8 +1693,6 @@ interface RCTRootViewFactoryConfiguration : public NSObject {
   public @property (assign) RCTLoadSourceForBridgeBlock loadSourceForBridge;
   public @property (assign) RCTLoadSourceForBridgeWithProgressBlock loadSourceForBridgeWithProgress;
   public @property (assign) RCTSourceURLForBridgeBlock sourceURLForBridge;
-  public @property (assign, readonly) BOOL fabricEnabled;
-  public @property (assign, readonly) BOOL turboModuleEnabled;
   public @property (weak) id<RCTJSRuntimeConfiguratorProtocol> jsRuntimeConfiguratorDelegate;
   public virtual instancetype initWithBundleURL:newArchEnabled:(NSURL* bundleURL, BOOL newArchEnabled);
   public virtual instancetype initWithBundleURLBlock:newArchEnabled:(RCTBundleURLBlock bundleURLBlock, BOOL newArchEnabled);

scripts/cxx-api/api-snapshots/ReactAppleNewarchCxx.api

@@ -1692,8 +1692,6 @@ interface RCTRootViewFactoryConfiguration : public NSObject {
   public @property (assign) RCTLoadSourceForBridgeBlock loadSourceForBridge;
   public @property (assign) RCTLoadSourceForBridgeWithProgressBlock loadSourceForBridgeWithProgress;
   public @property (assign) RCTSourceURLForBridgeBlock sourceURLForBridge;
-  public @property (assign, readonly) BOOL fabricEnabled;
-  public @property (assign, readonly) BOOL turboModuleEnabled;
   public @property (weak) id<RCTJSRuntimeConfiguratorProtocol> jsRuntimeConfiguratorDelegate;
   public virtual instancetype initWithBundleURL:newArchEnabled:(NSURL* bundleURL, BOOL newArchEnabled);
   public virtual instancetype initWithBundleURLBlock:newArchEnabled:(RCTBundleURLBlock bundleURLBlock, BOOL newArchEnabled);

scripts/cxx-api/api-snapshots/ReactAppleReleaseCxx.api

@@ -1693,8 +1693,6 @@ interface RCTRootViewFactoryConfiguration : public NSObject {
   public @property (assign) RCTLoadSourceForBridgeBlock loadSourceForBridge;
   public @property (assign) RCTLoadSourceForBridgeWithProgressBlock loadSourceForBridgeWithProgress;
   public @property (assign) RCTSourceURLForBridgeBlock sourceURLForBridge;
-  public @property (assign, readonly) BOOL fabricEnabled;
-  public @property (assign, readonly) BOOL turboModuleEnabled;
   public @property (weak) id<RCTJSRuntimeConfiguratorProtocol> jsRuntimeConfiguratorDelegate;
   public virtual instancetype initWithBundleURL:newArchEnabled:(NSURL* bundleURL, BOOL newArchEnabled);
   public virtual instancetype initWithBundleURLBlock:newArchEnabled:(RCTBundleURLBlock bundleURLBlock, BOOL newArchEnabled);