Add iOS App Clip Target to Expo Apps

Adds an iOS App Clip target to an Expo project end-to-end: creates the target (targets/clip/), wires up the Associated Domains entitlement (applinks: for the parent, appclips: for the Clip) on both the parent app and the Clip, generates and hosts the Apple App Site Association (AASA) file at /.well-known/apple-app-site-association (with appclips, webcredentials, and optional activitycontinuation blocks added on top of what bunx setup-safari prints for the parent app alone), adds a Smart App Banner meta tag via Expo Router's +html.tsx shell, deploys the AASA-hosting website with EAS Hosting, mirrors the parent app's Info.plist permission keys into the Clip's, and builds and submits both targets to TestFlight.

bun create target clip
bunx setup-safari

The parent app's bundle ID (com.<username>.<app-name>) determines the Clip's bundle ID automatically as <parent>.clip, and installs the underlying @bacons/apple-targets config plugin that generates the target's expo-target.config.js, Info.plist, AppDelegate.swift, and asset catalog.

Use it when the user mentions App Clip, AASA, apple-app-site-association, appclips, or a smart app banner, or wants to ship a lightweight iOS Clip invoked from a URL alongside their parent Expo app. It assumes an existing Expo project with a parent iOS app already configured - it is a Clip-addition workflow, not a from-scratch Expo or iOS app setup.

Inputs: the Expo project's app.json (for bundleIdentifier, appleTeamId, and associatedDomains), the domain that will host the AASA file, and the parent app's existing permission set (introspected via npx expo config --type introspect) to mirror into the Clip. Optional inputs are push-notification or location-service requirements that need matching NSAppClip request keys in the Clip's Info.plist, and a deploymentTarget of 17.6 or higher, since App Clips have a higher minimum size limit on iOS 17.6.

Outputs: a targets/clip/ App Clip target with its own bundle ID, entitlements, and Info.plist; an AASA file hosted at https://<domain>/.well-known/apple-app-site-association with matching appclips/webcredentials/activitycontinuation blocks; a Smart App Banner meta tag on every web route; and a TestFlight build containing both the parent app and the embedded Clip, each with its own provisioning profile under a shared Distribution Certificate. Optionally, a local Expo native module exposing navigator.appClip.prompt() so JS can detect it's running inside the Clip and show an install prompt for the full app.

Built on @bacons/apple-targets (EvanBacon/expo-apple-targets) for the target config plugin, EAS Hosting for deploying the AASA-serving website, EAS Build/Submit (bunx testflight, eas metadata:pull/eas metadata:push) for the TestFlight pipeline and App Store Connect metadata, and Expo Router (+html.tsx, Head) for the web shell and Apple Handoff continuation.

Expo and React Native teams shipping an iOS app who want a URL-invoked App Clip alongside their parent app - set up correctly with associated domains, AASA, App Store metadata, and TestFlight in one pass rather than reverse-engineering Apple's App Clip requirements from native docs.