fix(rustproxy-http): keep connection idle tracking alive during streaming and tune HTTP/2 connection lifetimes

rust/crates/rustproxy-http/src/counting_body.rs

@@ -25,6 +25,11 @@ pub struct CountingBody<B> {
     direction: Direction,
     /// Whether we've already reported the bytes (to avoid double-reporting on drop).
     reported: bool,
+    /// Optional connection-level activity tracker. When set, poll_frame updates this
+    /// to keep the idle watchdog alive during active body streaming (uploads/downloads).
+    connection_activity: Option<Arc<AtomicU64>>,
+    /// Start instant for computing elapsed ms for connection_activity.
+    activity_start: Option<std::time::Instant>,
 }
 
 /// Which direction the bytes flow.
@@ -53,9 +58,20 @@ impl<B> CountingBody<B> {
             source_ip,
             direction,
             reported: false,
+            connection_activity: None,
+            activity_start: None,
         }
     }
 
+    /// Set the connection-level activity tracker. When set, each data frame
+    /// updates this timestamp to prevent the idle watchdog from killing the
+    /// connection during active body streaming.
+    pub fn with_connection_activity(mut self, activity: Arc<AtomicU64>, start: std::time::Instant) -> Self {
+        self.connection_activity = Some(activity);
+        self.activity_start = Some(start);
+        self
+    }
+
     /// Report accumulated bytes to the metrics collector.
     fn report(&mut self) {
         if self.reported {
@@ -103,6 +119,10 @@ where
             Poll::Ready(Some(Ok(frame))) => {
                 if let Some(data) = frame.data_ref() {
                     this.counted_bytes.fetch_add(data.len() as u64, Ordering::Relaxed);
+                    // Keep the connection-level idle watchdog alive during body streaming
+                    if let (Some(activity), Some(start)) = (&this.connection_activity, &this.activity_start) {
+                        activity.store(start.elapsed().as_millis() as u64, Ordering::Relaxed);
+                    }
                 }
                 Poll::Ready(Some(Ok(frame)))
             }