fix: keep useUniwind in sync when compiled by React Compiler

[dlebedynskyi]

I ran into this in a monorepo where uniwind is a workspace package, so React Compiler compiles its source along with the app. With the compiler applied to src, the native tests showed useUniwind stuck on the first theme: ScopedTheme › useUniwind still read light after setTheme('dark'). Claude was fixing it.

When uniwind's source is compiled by React Compiler, useUniwind keeps returning the theme from its first render. Uniwind.setTheme('dark') re-renders the component, but theme stays light.

const Probe = () => {
    const { theme } = useUniwind()

    return <Text>{theme}</Text>
}

// renders "light"
Uniwind.setTheme('dark')
// re-renders, still "light"

useSnapshot reads Uniwind.currentTheme during render. The compiler treats getSnapshot() as pure and caches it on getSnapshot, which is a module-level function and never changes (babel-plugin-react-compiler 1.0.0):

const useSnapshot = (subscribe, getSnapshot) => {
  const $ = _c(9);
  const [snapshot, rerender] = useReducer(getSnapshot, undefined, getSnapshot);
  let t0;
  if ($[0] !== getSnapshot) {
    t0 = getSnapshot();
    $[0] = getSnapshot;
    $[1] = t0;
  } else {
    t0 = $[1];
  }
  const currentSnapshot = t0;
  // ...
  return currentSnapshot;
};

The theme listener still fires and rerender() runs, but the hook returns the cached $[1]. This affects native and web, since useUniwind.ts is shared.

The fix adds 'use no memo' to useSnapshot, as useStyle already does. Without the compiler the directive does nothing.

I also checked the other hooks that read runtime state under the compiler. useResolveClassNames and the withUniwind dependency hooks read the store only in reducers and effects, so they stay correct when compiled. useCSSVariable has the same render-time read, but the compiler skips it ("Reassigning initialized after render has completed"), so it isn't affected today. I can add the directive there too if you'd prefer to be explicit.

Tests

jest.config.native.js now runs the native suite as two projects: native (unchanged) and native-react-compiler, with src compiled by babel-plugin-react-compiler. The plugin is added as a devDependency at 1.0.0, the version bun.lock already has through babel-preset-expo. The only lockfile change is that devDependency line. Without the fix, native-react-compiler fails:

• ScopedTheme › useUniwind: expected dark, received light
• freeze › external stores catch up after a suspended tree is revealed: expected dark, received light

With the fix, both projects pass, 203/203 tests each. The web freeze test fails the same way under the compiler and passes with the fix. I checked that locally with a throwaway Vitest config that isn't part of this PR.

When it happens

Normal installs aren't affected. React Compiler's default sources skips paths that contain node_modules, and babel-preset-expo doesn't run the compiler on node modules either. It happens when the compiler reaches uniwind's source:

• uniwind resolves outside node_modules, for example a workspace package in a monorepo or a symlinked local checkout
• the app widens the compiler's sources to include node_modules

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