Skip native prop metadata for delegate-backed managers (#59296) #59296

Summary:

Add the default-off skipNativePropsForViewManagerWithDelegateAndroid feature flag. When enabled, ViewManager.getNativeProps() returns an empty map for managers with a non-null, non-generic delegate, avoiding unused manager and shadow-node prop metadata generation. Return a fresh mutable map so subclasses can safely extend super.getNativeProps(). The constants helper already omits NativeProps for an empty map; commands, events and custom constants are preserved.

Null and generic delegates keep the existing metadata path, including its legacy-architecture shadow-node handling. The flag must only be enabled when delegate-backed components use static view configs rather than runtime native prop metadata.

NativeProps queries reuse getOrCreateViewManagerDelegate(), sharing the same delegate with prop updates and commands. Make its lazy initialisation thread-safe with a volatile cache and double-checked synchronisation, leaving warm reads lock-free. Document that initialisation may occur on the JavaScript thread when this flag is enabled.

Regenerate all feature-flag bindings and cover enabled/disabled paths, generic and null delegates, marker-only managers, preserved constants, subclass prop extensions, independent mutable maps, existing-cache reuse and concurrent metadata/command initialisation.

Changelog:
[Android][Changed] - Add an opt-in optimisation to skip native prop metadata for delegate-backed view managers using static view configs.

Differential Revision: D126630163