feat: the trigger can ignore a noise band and reject HF before comparing

src/trigger.hpp

@@ -69,7 +69,8 @@ class TriggerEngine {
   /// buffer's, not a timer since arming -- the ring keeps filling with the trigger
   /// off, so the history is usually already there and waiting would be wrong.
   void configure(const TriggerConfig& cfg, const std::string& channel_name,
-                 double post_seconds, double pre_seconds, double oldest_s);
+                 double post_seconds, double pre_seconds, double oldest_s,
+                 double dt);
   /// Disarms without forgetting the configuration.
   void disarm() noexcept { armed_ = false; pending_ = false; }
   void arm(double now_s) noexcept;