diag(ios audio): settled-route probe (+0.4s/+1.2s) + live mode in route log

1.0.3 telemetry showed mode already == .voiceChat when earpiece still landed on
Speaker, and setSpeaker read the route synchronously (stale) right after the override.
So the mode re-pin alone may be insufficient and the sync read is unreliable.

1.0.5: keeps the .voiceChat re-pin, but stamps live mode into every route-change log
line and re-reads the SETTLED port+mode at +0.4s and +1.2s after each toggle (reported
in the next toggle's trail). This definitively answers whether WebKit flips to .videoChat
and where the route truly settles. native marker 1.0.5-settle.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

mobile/plugins/audio-route/ios/Sources/AudioRoutePlugin/AudioRoutePlugin.swift

@@ -5,20 +5,18 @@ import AVFoundation
 // Earpiece <-> speaker toggle for calls. Registered by cap sync as a real Capacitor plugin package, so it
 // shows up as window.Capacitor.Plugins.AudioRoute (an app-embedded class gets stripped in release builds).
 //
-// ROOT CAUSE (WebKit source: Source/WebCore/platform/audio/cocoa/MediaSessionManagerCocoa.mm, confirmed by
-// device telemetry): in a WKWebView the app does NOT own the AVAudioSession — WebKit's media process does.
-// While WebRTC capture is active it re-pins the session to .playAndRecord with mode .videoChat, and
-// .videoChat auto-implies .defaultToSpeaker. overrideOutputAudioPort(.none) means "revert to the mode
-// default", which under .videoChat is the LOUDSPEAKER — so .none alone can never reach the earpiece once
-// WebKit has flipped the mode. Our first .none won only because our .voiceChat mode was still in effect
-// (voiceChat's default route IS the receiver); after WebKit's reconfigure it latched to speaker.
-//
-// THE FIX: for earpiece, set mode .voiceChat FIRST, then overrideOutputAudioPort(.none). overrideOutputAudioPort
-// is a *transient* override (Apple QA1754) that every route/category change resets, and WebKit reconfigures on
-// capture start / setLocalDescription / ICE-connected / renegotiation — so we also observe routeChangeNotification
-// and re-assert (debounced, mismatch-only, capped) after WebKit's change settles. This reactive re-assert is the
-// only lever a WKWebView host has (WebKit's internal RTCAudioSession / useManualAudio is unreachable; WebKit bug
-// 167788 has left the app unable to disable WebKit's session management for 8+ years).
+// STATE OF THE INVESTIGATION (from device telemetry):
+//  * In a WKWebView the app does NOT own the AVAudioSession; WebKit's media process re-pins it while WebRTC
+//    capture is active. overrideOutputAudioPort is a *transient* override (Apple QA1754) that any route/category
+//    change resets, so we must re-assert on AVAudioSession.routeChangeNotification (debounced, mismatch-only, capped).
+//  * For earpiece, override(.none) reverts to the mode default — the RECEIVER only if the mode is .voiceChat.
+//    .videoChat implies .defaultToSpeaker => the default is the loudspeaker. So we pin .voiceChat before .none.
+//  * OPEN QUESTION this build answers: telemetry showed mode already == .voiceChat when earpiece still landed on
+//    Speaker, AND setSpeaker read the route SYNCHRONOUSLY right after the override (which can be stale). So this
+//    build adds a reliable SETTLED probe: it re-reads the actual output port + mode at +0.4s and +1.2s after each
+//    toggle, and stamps the live mode into every route-change log line. That tells us definitively whether WebKit
+//    flips to .videoChat and where the route truly settles — i.e. whether the mode re-pin works or we've hit the
+//    documented WKWebView ceiling (earpiece not reliably forceable on video calls).
 @objc(AudioRoutePlugin)
 public class AudioRoutePlugin: CAPPlugin, CAPBridgedPlugin {
     public let identifier = "AudioRoutePlugin"
@@ -28,22 +26,19 @@ public class AudioRoutePlugin: CAPPlugin, CAPBridgedPlugin {
     ]
 
     // Bump on every native change so telemetry identifies the running binary unambiguously.
-    private static let nativeTag = "1.0.4-mode"
+    private static let nativeTag = "1.0.5-settle"
 
     private var wantSpeaker = false          // desired output; source of truth, re-applied on route changes
     private var pending: DispatchWorkItem?   // debounced re-assert
     private var asserts = 0                   // re-assert count this toggle (capped, anti-thrash)
-    private var routeLog: [String] = []       // reason->port trail, returned to JS for diagnosis
+    private var routeLog: [String] = []       // reason->port/mode trail, returned to JS for diagnosis
 
-    // Real external outputs — when one of these is active and the user wants "earpiece", we must NOT force the
-    // built-in receiver (that would yank audio off the user's headset). Only correct the speaker<->receiver axis.
     private let accessoryPorts: [AVAudioSession.Port] = [
         .bluetoothHFP, .bluetoothA2DP, .bluetoothLE, .headphones, .headsetMic, .usbAudio, .carAudio, .airPlay
     ]
 
     override public func load() {
         let session = AVAudioSession.sharedInstance()
-        // NO .defaultToSpeaker — .voiceChat's default route is the receiver, so the port override decides output.
         try? session.setCategory(.playAndRecord, mode: .voiceChat, options: [.allowBluetooth, .allowBluetoothA2DP])
         try? session.setActive(true)
         NotificationCenter.default.addObserver(self, selector: #selector(routeChanged(_:)),
@@ -60,65 +55,74 @@ public class AudioRoutePlugin: CAPPlugin, CAPBridgedPlugin {
         }
     }
 
-    private func ports() -> String {
-        let outs = AVAudioSession.sharedInstance().currentRoute.outputs.map { $0.portType.rawValue }
-        return outs.isEmpty ? "(none)" : outs.joined(separator: "+")
+    private func modeShort(_ m: AVAudioSession.Mode) -> String {
+        if m == .voiceChat { return "vc" }
+        if m == .videoChat { return "vid" }
+        if m == .default { return "def" }
+        return "oth"
+    }
+
+    // Actual output port(s) + live mode — the ground-truth snapshot.
+    private func snap() -> String {
+        let s = AVAudioSession.sharedInstance()
+        let outs = s.currentRoute.outputs.map { $0.portType.rawValue }
+        return (outs.isEmpty ? "(none)" : outs.joined(separator: "+")) + "/" + modeShort(s.mode)
     }
 
     private func log(_ s: String) {
         routeLog.append(s)
-        if routeLog.count > 16 { routeLog.removeFirst(routeLog.count - 16) }
+        if routeLog.count > 18 { routeLog.removeFirst(routeLog.count - 18) }
     }
 
     @objc private func routeChanged(_ note: Notification) {
         let raw = (note.userInfo?[AVAudioSessionRouteChangeReasonKey] as? UInt) ?? 0
-        log("\(reasonName(raw))>\(ports())")
-        // Re-assert AFTER WebKit's change settles; coalesce bursts into one late assert so we act last.
+        log("\(reasonName(raw))>\(snap())")
         pending?.cancel()
         let work = DispatchWorkItem { [weak self] in self?.applyRoute() }
         pending = work
         DispatchQueue.main.asyncAfter(deadline: .now() + 0.25, execute: work)
     }
 
-    // Nudge the route toward the desired output, acting ONLY on a real built-in speaker<->receiver mismatch so
-    // our own override (which itself fires a route change) self-terminates instead of looping.
     private func applyRoute() {
-        guard asserts < 6 else { log("cap"); return }   // anti-thrash: give up rather than ping-pong forever
+        guard asserts < 6 else { log("cap"); return }
         let s = AVAudioSession.sharedInstance()
         let outs = s.currentRoute.outputs
         let onSpeaker = outs.contains { $0.portType == .builtInSpeaker }
         let onAccessory = outs.contains { accessoryPorts.contains($0.portType) }
-        if onAccessory && !wantSpeaker { log("skipAcc"); return }   // leave a real headset/BT alone
+        if onAccessory && !wantSpeaker { log("skipAcc"); return }
         do {
             if wantSpeaker {
                 if !onSpeaker { asserts += 1; try s.overrideOutputAudioPort(.speaker); log("assert>spk") }
             } else if onSpeaker {
                 asserts += 1
-                // .none alone can't beat WebKit's .videoChat default (= speaker). Re-pin voiceChat first so the
-                // "revert to default" the override does actually resolves to the RECEIVER.
+                // .none reverts to the mode default; make that the RECEIVER by pinning .voiceChat first.
                 if s.category != .playAndRecord {
                     try s.setCategory(.playAndRecord, mode: .voiceChat, options: [.allowBluetooth, .allowBluetoothA2DP])
                     log("repinCat")
                 } else if s.mode != .voiceChat {
-                    try s.setMode(.voiceChat)
-                    log("repinMode")
+                    try s.setMode(.voiceChat); log("repinMode")
                 }
                 try s.overrideOutputAudioPort(.none)
-                log("assert>rcv")
+                log("assert>rcv:\(snap())")
             }
         } catch { log("assertErr") }
     }
 
+    // Re-read the SETTLED route a beat after the override, since the immediate read can be stale.
+    private func scheduleSettleProbe() {
+        DispatchQueue.main.asyncAfter(deadline: .now() + 0.4) { [weak self] in self?.log("s4>\(self?.snap() ?? "")") }
+        DispatchQueue.main.asyncAfter(deadline: .now() + 1.2) { [weak self] in self?.log("s12>\(self?.snap() ?? "")") }
+    }
+
     private func diag(_ applied: String) -> [String: Any] {
         let s = AVAudioSession.sharedInstance()
         return [
             "route": applied,
             "native": AudioRoutePlugin.nativeTag,
-            "outputs": ports(),
+            "outputs": snap(),
             "category": s.category.rawValue,
-            "mode": s.mode.rawValue,
             "opts": Int(s.categoryOptions.rawValue),
-            "log": routeLog.joined(separator: ",")   // route-change trail since the previous toggle
+            "log": routeLog.joined(separator: ",")   // trail (incl. settled probes) since the previous toggle
         ]
     }
 
@@ -127,14 +131,13 @@ public class AudioRoutePlugin: CAPPlugin, CAPBridgedPlugin {
         asserts = 0
         let s = AVAudioSession.sharedInstance()
         do {
-            // Earpiece: pin .voiceChat first so the very first press is correct even if WebKit already flipped
-            // the mode to .videoChat. Speaker: override(.speaker) works under any mode, no mode change needed.
             if !wantSpeaker && s.category == .playAndRecord && s.mode != .voiceChat {
                 try s.setMode(.voiceChat)
             }
             try s.overrideOutputAudioPort(wantSpeaker ? .speaker : .none)
+            scheduleSettleProbe()                     // settled reads land in the NEXT toggle's trail
             let out = diag(wantSpeaker ? "speaker" : "earpiece")
-            routeLog.removeAll()   // reset the trail; next toggle reports what happened in between
+            routeLog.removeAll()
             call.resolve(out)
         } catch {
             call.reject(error.localizedDescription)