doc:monitor: clarify direction traced with default aggregation level

We do rely on monitorAggregation value to know which/when tracing
network packets in our datapath. The current default `medium` level allows
tracing ONLY send packets matching the conditions correctly described
in the documentation. However, prior to this commit, we did not specify
the send direction only in its definition, causing potential misinterpretation.

Signed-off-by: Simone Magnani <simone.magnani@isovalent.com>

Author: smagnani96

Documentation/network/kubernetes/configuration.rst

@@ -49,9 +49,9 @@ to your preferences:
 
   - ``none`` - Generate a tracing event on every receive and send packet.
   - ``low`` - Generate a tracing event on every send packet.
-  - ``medium`` - Generate a tracing event on every new connection, any time a
-    packet contains TCP flags that have not been previously seen for the packet
-    direction, and on average once per ``monitor-aggregation-interval``
+  - ``medium`` - Generate a tracing event for send packets only on every new
+    connection, any time a packet contains TCP flags that have not been previously
+    seen for the packet direction, and on average once per ``monitor-aggregation-interval``
     (assuming that a packet is seen during the interval). Each direction tracks
     TCP flags and report interval separately. If Cilium drops a packet, it will
     emit one event per packet dropped.

Documentation/operations/performance/tuning.rst

@@ -447,9 +447,10 @@ should consider increasing the aggregation interval or rate limiting events.
 Increase Aggregation Interval
 -----------------------------
 
-By default Cilium generates a tracing event on every new connection, any time a packet
-contains TCP flags that have not been previously seen for the packet direction, and on
-average once per ``monitor-aggregation-interval``, which defaults to 5 seconds.
+By default Cilium generates a tracing event for send packets only on every new
+connection, any time a packet contains TCP flags that have not been previously
+seen for the packet direction, and on average once per ``monitor-aggregation-interval``,
+which defaults to 5 seconds.
 
 Depending on your network traffic patterns, the re-emitting of trace events per
 aggregation interval can make up a large part of the total events. Increasing the