chore: release v0.4.1-beta.3

[txbrown]

Beta 3 release with iOS engine-lifecycle hardening, React Native 0.85.3 compatibility, and Android 16 KB page-size support.

Changes since 0.4.1-beta.2

Improvements

• React Native 0.85.3 — updates the example app and native toolchains; brings fmt 12.1.0 compatibility with Apple Clang C++20.
• Android: support 16 KB page sizes.

Bug Fixes

• iOS: serialize runtime cleanup, dispatch AVAudioEngine access to the main thread, and guard cold-engine calls.