otel: waterfall shows latest REAL trace (skip dashboard's own poll routes)

lib/host/otel.sx

@@ -398,10 +398,19 @@
      :spans (len (otel/trace-spans trace-id))}))
 (define otel/recent-traces
   (fn () (reverse (map otel/trace-summary (otel/-trace-ids)))))
+;; the dashboard's own endpoints — excluded from the "latest trace" so the
+;; waterfall shows the latest REAL request (a page) instead of the 3s poll.
+(define otel/-self-route?
+  (fn (route)
+    (or (= route "/otel") (= route "/otel/fragment") (= route "/otel/stream"))))
+;; the most recent NON-self trace (fall back to any trace if all are self).
 (define otel/latest-trace
   (fn ()
-    (let ((r (otel/recent)))
-      (if (empty? r) nil (get (last r) :trace)))))
+    (let ((real (filter (fn (s) (not (otel/-self-route? (get (get s :attrs) :http.route)))) (otel/recent))))
+      (cond
+        ((not (empty? real)) (get (last real) :trace))
+        ((not (empty? (otel/recent))) (get (last (otel/recent)) :trace))
+        (else nil)))))
 
 ;; ── SSE span events (SXTP) ────────────────────────────────────────────
 (define otel/span-event