session start event (#467)

crates/server/src/main.rs

@@ -41,6 +41,9 @@ async fn main() -> Result<(), VibeKanbanError> {
     deployment.update_sentry_scope().await?;
     deployment.cleanup_orphan_executions().await?;
     deployment.spawn_pr_monitor_service().await;
+    deployment
+        .track_if_analytics_allowed("session_start", serde_json::json!({}))
+        .await;
 
     let app_router = routes::router(deployment);