Add the sse-websocket module

sse-websocket/docs/output/sse-lifecycle.txt

@@ -0,0 +1,23 @@
+=== GET /sse/silent?timeoutMs=1200 : whole response ===
+| HTTP/1.1 200 
+| Content-Type: text/event-stream
+| Transfer-Encoding: chunked
+| Date: Thu, 03 Sep 2026 18:59:34 GMT
+| Connection: close
+| 
+| 1f
+| event:hello
+| data:then silence
+| 
+| 
+| 0
+| 
+=== stream ended after ~1697 ms ===
+=== registry.timedOut(): 0 -> 1 ===
+
+=== client closed the socket, then: ===
+broadcasts before the write failed : 2
+registry.sendsOk                   : 1
+registry.sendsFailed               : 0 -> 1
+registry.open                      : 0
+=== writes that appeared to succeed after the client was gone: 1 ===