Add os.Logger diagnostics to SyncEngine.connect()

Workouts/Sync/SyncEngine.swift

@@ -1,6 +1,7 @@
 import Foundation
 import SwiftData
 import Observation
+import os
 
 enum ICloudStatus: Equatable {
     case checking
@@ -23,6 +24,7 @@ final class SyncEngine {
     /// this to push fresh state to the watch.
     var onCacheChanged: (() -> Void)?
 
+    private let log = Logger(subsystem: "dev.rzen.indie.Workouts", category: "sync")
     private let modelContainer: ModelContainer
     private var fileManager: ICloudFileManager?
     private var monitor: ICloudFileMonitor?
@@ -42,14 +44,17 @@ final class SyncEngine {
         connectAttempt += 1
         let attempt = connectAttempt
         iCloudStatus = .checking
+        log.info("connect[\(attempt)]: resolving container \(Self.containerIdentifier, privacy: .public)")
 
         let url = await Task.detached {
             FileManager.default.url(forUbiquityContainerIdentifier: Self.containerIdentifier)
         }.value
         guard let containerURL = url else {
+            log.error("connect[\(attempt)]: ubiquity container URL is nil → unavailable (iCloud Drive off, or container not provisioned)")
             if attempt == connectAttempt { iCloudStatus = .unavailable }
             return
         }
+        log.info("connect[\(attempt)]: container URL = \(containerURL.path, privacy: .public)")
 
         let fm = ICloudFileManager(containerURL: containerURL)
 
@@ -57,15 +62,18 @@ final class SyncEngine {
             try? await Task.sleep(for: .seconds(20))
             guard let self, !Task.isCancelled else { return }
             if self.iCloudStatus == .checking, attempt == self.connectAttempt {
+                self.log.error("connect[\(attempt)]: timed out after 20s — first container file op blocked (dataless container?)")
                 self.iCloudStatus = .unavailable
             }
         }
+        log.info("connect[\(attempt)]: preparing directories…")
         await fm.prepareDirectories()
         timeout.cancel()
         guard attempt == connectAttempt else { return }
 
         self.fileManager = fm
         iCloudStatus = .available
+        log.info("connect[\(attempt)]: directories ready → available")
         WorkoutsModelContainer.persistCurrentIdentityToken()
 
         await reconcile()