fix(tuic): client speed display and certificate button layout (#6723)

* fix(tuic): restore client speed and certificate layout

* docs(tuic): clarify native runtime and protocol behavior

* fix(websocket): preserve traffic updates from independent sources

* fix(docs): sync websocket traffic schema and drop restating TUIC tests

docs/public/openapi.json still described the old traffic event, without
clientTrafficSource/clientTrafficIntervalMs or the TUIC oneOf branch, so
the docs site showed a payload the panel no longer sends. No check
covers that copy.

The TUIC certificate layout test and the TUIC speed payload test only
read back the literals the code writes, so neither could fail on a real
regression. Both are removed, along with the className that existed only
for the layout test.

---------

Co-authored-by: MHSanaei <ho3ein.sanaei@gmail.com>

internal/web/websocket/hub.go

@@ -94,10 +94,12 @@ func NewHub() *Hub {
 	}
 }
 
+// Traffic messages carry independent partial updates from Xray, TUIC, and node
+// polling jobs. Throttling by message type would silently discard one source
+// when two jobs publish within the throttle window.
 var throttledMessageTypes = map[MessageType]struct{}{
 	MessageTypeInbounds:    {},
 	MessageTypeOutbounds:   {},
-	MessageTypeTraffic:     {},
 	MessageTypeClientStats: {},
 }