ios: trace raw core->UI subs payload + actual app state in subs poll

Add a second tracing layer to find why the chat-list indicator stays empty
while the servers-summary detail view shows 100%:

- API.swift sendSimpleXCmd: log the raw bytes the core returns for the
  "/get subs total" query, before decoding. getAgentSubsTotal is sent with
  log:false, so nothing currently records its raw response; and
  decodeAPIResult swallows decode errors (catch {}), so a JSON/shape
  mismatch would silently produce empty values. This shows what the core
  actually sends vs the decoded ssActive/ssPending we already log.
- ChatListView poll: log the actual AppChatState value (not just the
  active bool) when a tick is gated out, to see which state it is stuck in
  in the lock / return-from-background cases.

apps/ios/Shared/Views/ChatList/ChatListView.swift

@@ -605,7 +605,8 @@ struct SubsStatusIndicator: View {
         task = Task {
             logger.debug("SUBS_TRACE poll loop: started")
             while !Task.isCancelled {
-                let appActive = AppChatState.shared.value == .active
+                let appState = AppChatState.shared.value
+                let appActive = appState == .active
                 let running = ChatModel.shared.chatRunning == true
                 if appActive, running {
                     do {
@@ -620,7 +621,7 @@ struct SubsStatusIndicator: View {
                         logger.error("getSubsTotal error: \(responseError(error))")
                     }
                 } else {
-                    logger.debug("SUBS_TRACE poll skipped tick: appActive=\(appActive) chatRunning=\(running) (gated out, not fetching)")
+                    logger.debug("SUBS_TRACE poll skipped tick: appState=\(appState.rawValue) appActive=\(appActive) chatRunning=\(running) (gated out, not fetching)")
                 }
                 try? await Task.sleep(nanoseconds: 1_000_000_000) // Sleep for 1 second
             }

apps/ios/SimpleXChat/API.swift

@@ -114,9 +114,17 @@ public func resetChatCtrl() {
 @inline(__always)
 public func sendSimpleXCmd<R: ChatAPIResult>(_ cmd: ChatCmdProtocol, _ ctrl: chat_ctrl? = nil, retryNum: Int32 = 0) -> APIResult<R> {
     if let d = sendSimpleXCmdStr(cmd.cmdString, ctrl, retryNum: retryNum) {
-        decodeAPIResult(d)
+        // SUBS_TRACE: log the exact bytes the core sends back for the subs-total query,
+        // before any decoding — this is what the UI actually receives from the core.
+        if cmd.cmdString.hasPrefix("/get subs total") {
+            logger.debug("SUBS_TRACE raw core->UI for '\(cmd.cmdString)': \(dataToString(d))")
+        }
+        return decodeAPIResult(d)
     } else {
-        APIResult.error(.invalidJSON(json: nil))
+        if cmd.cmdString.hasPrefix("/get subs total") {
+            logger.debug("SUBS_TRACE raw core->UI for '\(cmd.cmdString)': nil (core returned no data)")
+        }
+        return APIResult.error(.invalidJSON(json: nil))
     }
 }