EventTarget-based event dispatching (#56427)

Summary:
Pull Request resolved: #56427

Changelog: [internal]

## Context

The current React Native Fabric renderer uses a legacy plugin-based
event system (ResponderEventPlugin, ReactNativeBridgeEventPlugin,
pooled SyntheticEvent objects) that duplicates dispatch logic already
provided by the W3C EventTarget API. This adds complexity, prevents
alignment with the Web platform, and blocks EventTarget-based features.

## Changes

Behind the `enableNativeEventTargetEventDispatching` flag, native events
are dispatched through `dispatchTrustedEvent` on the public instance
tree instead of the legacy plugin system. Event handler props are
extracted from `canonical.currentProps` at dispatch time via a
declarative listener hook on EventTarget — no `addEventListener`
registration at commit time.

The responder system is fully self-contained: it walks the public
instance tree directly for negotiation, calls handlers from props, and
inspects return values inline (e.g. `onResponderGrant` returning `true`
blocks native). It has no EventTarget coupling and no commit-time cost.

Reviewed By: javache, jackpope

Differential Revision: D100462547

fbshipit-source-id: f6422544ad0ea091c26a3c2abf82dc3679d706f3

Author: rubennorte

packages/react-native/Libraries/ReactNative/FabricUIManager.js

@@ -92,6 +92,11 @@ export interface Spec {
     /* width: */ number,
     /* height: */ number,
   ];
+  +setIsJSResponder: (
+    node: Node | NativeElementReference,
+    isJSResponder: boolean,
+    blockNativeResponder: boolean,
+  ) => void;
   +unstable_DefaultEventPriority: number;
   +unstable_DiscreteEventPriority: number;
   +unstable_ContinuousEventPriority: number;
@@ -124,6 +129,7 @@ const CACHED_PROPERTIES = [
   'dispatchCommand',
   'compareDocumentPosition',
   'getBoundingClientRect',
+  'setIsJSResponder',
   'unstable_DefaultEventPriority',
   'unstable_DiscreteEventPriority',
   'unstable_ContinuousEventPriority',

packages/react-native/Libraries/ReactPrivate/ReactNativePrivateInterface.js

@@ -8,9 +8,8 @@
  * @format
  */
 
+import typeof dispatchNativeEvent from '../../src/private/renderer/events/dispatchNativeEvent';
 import typeof CustomEvent from '../../src/private/webapis/dom/events/CustomEvent';
-import typeof {setEventInitTimeStamp} from '../../src/private/webapis/dom/events/internals/EventInternals';
-import typeof {dispatchTrustedEvent} from '../../src/private/webapis/dom/events/internals/EventTargetInternals';
 import typeof BatchedBridge from '../BatchedBridge/BatchedBridge';
 import typeof legacySendAccessibilityEvent from '../Components/AccessibilityInfo/legacySendAccessibilityEvent';
 import typeof TextInputState from '../Components/TextInput/TextInputState';
@@ -135,12 +134,8 @@ module.exports = {
     return require('../ReactNative/ReactFabricPublicInstance/ReactFabricPublicInstance')
       .getInternalInstanceHandleFromPublicInstance;
   },
-  get dispatchTrustedEvent(): dispatchTrustedEvent {
-    return require('../../src/private/webapis/dom/events/internals/EventTargetInternals')
-      .dispatchTrustedEvent;
-  },
-  get setEventInitTimeStamp(): setEventInitTimeStamp {
-    return require('../../src/private/webapis/dom/events/internals/EventInternals')
-      .setEventInitTimeStamp;
+  get dispatchNativeEvent(): dispatchNativeEvent {
+    return require('../../src/private/renderer/events/dispatchNativeEvent')
+      .default;
   },
 };