feat:migrate to standard navigation shared adapter

[oleksandrzavarzin-callstack]

What

Expo SDK 56 dropped Expo Router's dependency on @react-navigation/* in favour of a vendored fork. @bottom-tabs/react-navigation imports the real thing, so on SDK 56+ two copies of React Navigation load and their contexts stop lining up.

This moves the tab view into a new framework-agnostic package, @bottom-tabs/standard-navigation, built on the standard-navigation contract. One implementation, two adapters:

Expo SDK	Package	Integration
56+	@bottom-tabs/standard-navigation	unstable_createStandardRouterNavigator
52 to 55	@bottom-tabs/react-navigation	withLayoutContext

@bottom-tabs/react-navigation's public API is unchanged - same exports, same types, same theme-derived tint defaults. It becomes a thin adapter over the shared view.

Notable

• Dropped the color dependency for React Native's processColor. color is ESM-only, so every consumer who writes tests had to patch transformIgnorePatterns before Jest would run at all.
• The peer on @react-navigation/native stays at >=7. An earlier revision raised it to >=7.3.0, which broke npm install outright for SDK 52-55 apps locked below that - and nothing on that path needs 7.3.
• NativeBottomTabsContent carries its event map and navigator props on phantom type-only properties. Without them an integrator loses every navigator prop at the call site: tabBarActiveTintColor and friends become type errors.
• unstable_createStandardRouterNavigator is marked unstable by Expo and may change between minors. We deliberately don't call it ourselves, so a break stays in app code.
• On the Expo Router path a custom tabBar receives { state, descriptors, actions, emitter } rather than a navigation object, so @react-navigation/bottom-tabs' BottomTabBar can't be used there. The React Navigation path is unaffected.

How to test

yarn && yarn build
yarn test        # 96 tests across 5 workspaces
yarn lint && yarn typecheck

apps/expo-router-test runs one assertion suite against both adapters under a real Expo Router tree, with a console spy that fails on any warning or error.

Verified on an app scaffolded from create-expo-app --template default@sdk-57 (Expo 57, React Native 0.86.3, React 19.2.3):

• iOS 26 and Android 17 - builds and bundles, Liquid Glass and Material 3 tab bars render with tint and badge, tapping routes between screens. No JS warnings or errors.
• @react-navigation/* is absent from node_modules entirely, so there's no second copy to line up - everything resolves through Expo Router's vendored fork.

The SDK 52-55 path was checked separately: the documented withLayoutContext recipe typechecks clean against a real expo-router@55 install, at both 7.1.33 and 7.3.0.

Screenshots

iOS 26	Android 17

[thiagobrez]

Why do we need to drop this dependency? I'm concerned we might get regressions

[thiagobrez]

Suggested change

	"description": "Framework-agnostic native bottom tabs navigator built on the standard-navigation contract",
	"description": "Framework-agnostic native bottom tabs navigator",

[thiagobrez]

I think we can remove this whole test

[thiagobrez]

I have two requested changes before approving:

1. The switch from color to processColor changes the inactive tint for themes with translucent colors. mixColors averages RGB channels without alpha weighting. For example, with transparent text and a white card, the previous Color(colors.text).mix(Color(colors.card), 0.5).hex() returns #FFFFFF, while the new implementation returns #808080. Please roll back the removal of the color dependency and restore the previous mixing behavior to avoid a visible regression. A translucent-color regression test would help protect it.

2. The new test suites are not run by the PR's CI workflow; it runs lint, typecheck, and builds, but no yarn test. Please add a CI test step or job so these tests gate future changes.