Avoid exception-based nativeID parsing

[zxrl]

Summary

Follow-up to #7163.

React Native exposes nativeID as a string and uses non-numeric values internally. The legacy layout animation proxy currently parses every non-empty nativeID with stoi and relies on exceptions to reject unrelated IDs. In iOS applications whose native link graph contains code compiled with -fno-exceptions, that invalid parse can terminate the process instead of reaching the catch block.

This change moves nativeID parsing into LayoutAnimationsProxyCommon and uses the existing non-throwing digit validation from the experimental proxy. Both layout animation proxies now share one parser, non-numeric IDs are ignored, and numeric Reanimated IDs continue transferring their animation configuration.

Test plan

Formatting and common C++ validation:

clang-format --dry-run --Werror \
  packages/react-native-reanimated/Common/cpp/reanimated/LayoutAnimations/LayoutAnimationsProxyCommon.{cpp,h} \
  packages/react-native-reanimated/Common/cpp/reanimated/LayoutAnimations/LayoutAnimationsProxy_Experimental.{cpp,h} \
  packages/react-native-reanimated/Common/cpp/reanimated/LayoutAnimations/LayoutAnimationsProxy_Legacy.{cpp,h}

cd packages/react-native-reanimated
../../scripts/validate-common.sh

Physical iOS reproduction uses React Native 0.86, Fabric, Hermes, and a native dependency graph containing -fno-exceptions. Mounting a view with a non-numeric nativeID while Reanimated processes layout insertions previously aborted in LayoutAnimationsProxy_Legacy::transferConfigFromNativeID through std::__1::stoi.

Minimal affected view:

import Animated, { FadeIn } from 'react-native-reanimated';

export default function App() {
  return <Animated.View entering={FadeIn} nativeID="profile-avatar" />;
}

After this change, the non-numeric ID is ignored without throwing. Numeric IDs still reach LayoutAnimationsManager::transferConfigFromNativeID.

[bartlomiejbloniarz]

Good catch, I forgot to backport it to Legacy! Why is it a draft still? Do you intend to do more changes?