Delete legacy RCTNativeAnimatedModule from RN iOS

[christophpurrer]

Summary:
The Old Architecture has been deleted from React Native iOS, which makes the
legacy RCTNativeAnimatedModule unreachable:

• Its JS spec only requests 'NativeAnimatedModule' when
  shouldUseTurboAnimatedModule() is false, but ReactInstance.cpp sets
  RN$Bridgeless = true unconditionally on iOS, so that branch never runs.
• Its only entry points were -setBridge: and RCTUIManagerObserver, and
  RCTBridge is now an all-nil stub with RCTCxxBridge deleted.
• Nothing referenced it by filename except a single legacy = True Buck
  plugin provider.

iOS Animated is served by RCTNativeAnimatedTurboModule (bridgeless ObjC) and
by the C++ facebook::react::AnimatedModule behind cxxNativeAnimatedEnabled().

Deleted RCTNativeAnimatedModule.h / .mm and its registrations: the
legacy = True react_module_plugin_providers entry in
xplat/js/react-native-github/BUCK, the RCTNativeAnimatedModuleCls shim in
the generated RCTAnimationPlugins.{h,mm}, the getCoreModuleClasses()
entry in RCTBridge.mm, the headers-include-baseline.json entries, and the
js1 rn-arch codemod skip-list entry.

With the last bridge-dependent Animated consumer gone, also stripped the dead
bridge plumbing it was the only reason for:

• RCTNativeAnimatedNodesManager -initWithBridge:surfacePresenter: loses
  bridge:.
• RCTPropsAnimatedNode -connectToView:viewName:bridge:surfacePresenter: loses
  bridge: and the RCTUIManager fallback in -updateView, which collapses to
  the single synchronouslyUpdateViewOnUIThread:props: call.
• viewName: goes too, since it was only used to look up a legacy view
  manager. The C++ (connectAnimatedNodeToView(Tag, Tag)) and Kotlin
  (connectAnimatedNodeToView(animatedNodeTag, viewTag)) nodes managers already
  take two arguments, and the sole remaining ObjC caller passed nil.

RCTNativeAnimatedTurboModule is deliberately NOT renamed back to
RCTNativeAnimatedModule — that is a much wider rename, best done separately.

Changelog: [INTERNAL]

Differential Revision: D115663619

[meta-codesync]

@christophpurrer has exported this pull request. If you are a Meta employee, you can view the originating Diff in D115663619.