Add extra analytics for notification performance (#6237)

* Add extra analytics for notification performance

Add technical spans to track how long a notification fetching work request takes to run, then how long it takes to actually fetch the events for the notifications

* Remove `withContext(io)` for `FetchNotificationsWorker`

The default `Dispatchers.Default` dispatcher used should be good enough and more performant

* Add network check span

services/analyticsproviders/api/src/main/kotlin/io/element/android/services/analyticsproviders/api/AnalyticsTransactions.kt

@@ -37,6 +37,12 @@ object AnalyticsTransactions {
         operation = "ux",
         description = "Send to sent state in timeline",
     )
+
+    val pushToNotification = TransactionDefinition(
+        name = "Push to notification",
+        operation = "push_to_notification",
+        description = "Time from receiving a push notification until it's displayed",
+    )
 }
 
 data class TransactionDefinition(