Move subagents into session side panel

app/androidApp/src/main/kotlin/com/example/aiapp/Api.kt

@@ -236,14 +236,6 @@ data class SessionSummary(
     val started: Double,
     /** Latest measured number of live background tasks; zero also covers older servers. */
     val backgroundTasks: Int,
-    /**
-     * How many subagents this session has, however their own status now reads.
-     *
-     * A directory listing on the server rather than a status read per subagent, so the list stays
-     * cheap; the per-subagent state is only fetched when the card is expanded. Zero on a server
-     * that predates subagents, so this app still opens against one.
-     */
-    val subagents: Int,
 )
 
 private fun parseSession(session: JSONObject) =
@@ -276,7 +268,6 @@ private fun parseSession(session: JSONObject) =
         lastActivity = session.getDouble("lastActivity"),
         started = session.optDouble("started", session.getDouble("lastActivity")),
         backgroundTasks = session.optInt("backgroundTasks", 0),
-        subagents = session.optInt("subagents", 0),
     )
 
 fun fetchSessions(settings: ServerSettings): List<SessionSummary> =