feat: capture the screen in-app with ScreenCaptureKit (drop ReplayKit extension)

Replace the ReplayKit broadcast upload extension with an in-app iOS 27 ScreenCaptureKit pipeline — capture, compositing, and publishing all run in-process. Move the process-agnostic RTMP/SRT/WHIP publishers into the app target, delete the extension + host-app keepalive machinery, bump to iOS 27 with the screen-capture background mode, add a StreamCoreTests Swift Testing suite, a Haptics helper, and advance the vendored HaishinKit pointer for VideoToolbox invalid-session recovery on background transitions.

CI runs the StreamCore test suite; the full app needs the iOS 27 SDK (unavailable on GitHub runners) and is verified on a physical device.

Author: joeblau

.github/workflows/ci.yml

@@ -10,8 +10,8 @@ concurrency:
   cancel-in-progress: true
 
 jobs:
-  build:
-    name: Build (iOS Simulator)
+  test:
+    name: StreamCore tests (iOS Simulator)
     runs-on: macos-26
     steps:
       - name: Checkout
@@ -30,10 +30,17 @@ jobs:
       - name: Generate Xcode project
         run: xcodegen generate
 
-      - name: Build
+      # The full Stream app requires the iOS 27 SDK (ScreenCaptureKit + the
+      # AVAudioInputNode throwing-tap API), which GitHub runners do not ship
+      # yet — the newest hosted Xcode (26.x) only carries the iOS 26 SDK. Until
+      # runners gain Xcode 27, CI validates the pure StreamCore logic and its
+      # test suite (both pinned to an iOS 18 floor in project.yml, so they build
+      # and run on the runner's iOS 26 simulators). The app itself is verified
+      # on a physical iOS 27 device.
+      - name: Test StreamCore
         run: |
-          xcodebuild build \
-            -scheme Stream \
-            -destination 'generic/platform=iOS Simulator' \
+          xcodebuild test \
+            -scheme StreamCoreTests \
+            -destination 'platform=iOS Simulator,OS=latest,name=iPhone 17' \
             CODE_SIGNING_ALLOWED=NO \
             -skipPackagePluginValidation

README.md

@@ -75,31 +75,18 @@ final class AudioInputProvider {
 
     private func configureAndEnumerate() {
         let session = AVAudioSession.sharedInstance()
-        // Never ACTIVATE a second .playAndRecord session while a broadcast is
-        // live — activation can interrupt the extension's session and steal the
-        // Bluetooth HFP route mid-stream. Setting the category alone (without
-        // setActive) is enough to surface BT ports in availableInputs, so the
-        // picker still works while live. (isLive has heartbeat granularity, so
-        // a broadcast started milliseconds ago may enumerate the old way once —
-        // an accepted trade-off versus stealing the extension's route.)
-        guard !BroadcastStateStore.isLive() else {
-            for options in Self.bluetoothOptionLadder() {
-                do {
-                    try session.setCategory(.playAndRecord, mode: .default, options: options)
-                    break
-                } catch {
-                    continue
-                }
+        // Setting the category is sufficient to enumerate Bluetooth inputs. Do
+        // not activate merely for enumeration; activation is asynchronous on
+        // iOS 27 and can disturb ScreenCaptureKit's microphone session.
+        for options in Self.bluetoothOptionLadder() {
+            do {
+                try session.setCategory(.playAndRecord, mode: .default, options: options)
+                break
+            } catch {
+                continue
             }
-            enumerate(from: session)
-            return
         }
-        Self.activateBluetoothRecording(session)
         enumerate(from: session)
-        // Enumeration captured — release the route immediately. Holding an
-        // activated record session for the app's entire lifetime competed with
-        // the extension's session across broadcast restarts.
-        try? session.setActive(false, options: .notifyOthersOnDeactivation)
     }
 
     private func enumerate(from session: AVAudioSession) {
@@ -121,11 +108,11 @@ final class AudioInputProvider {
     /// mics weren't selectable). Tries the richest Bluetooth option set first and
     /// degrades, so one unsupported option never blocks enumeration.
     @discardableResult
-    static func activateBluetoothRecording(_ session: AVAudioSession) -> Bool {
+    static func activateBluetoothRecording(_ session: AVAudioSession) async -> Bool {
         for options in bluetoothOptionLadder() {
             do {
                 try session.setCategory(.playAndRecord, mode: .default, options: options)
-                try session.setActive(true)
+                try session.setActive(true, options: [])
                 return true
             } catch {
                 continue