feat: add SSE process filter for stream parsing

noise-sse.el

@@ -50,5 +50,26 @@ Returns nil for empty or invalid events."
               (json-parse-string json-str)
             (error nil)))))))
 
+(defvar noise-sse--buffer ""
+  "Buffer for partial SSE event data.")
+
+(defun noise-sse--filter (proc string)
+  "Process filter for SSE connection.
+Buffers incoming STRING and processes complete events."
+  (setq noise-sse--buffer (concat noise-sse--buffer string))
+  (while (string-match "\n\n" noise-sse--buffer)
+    (let ((event-end (match-beginning 0))
+          (event-start 0))
+      (let ((event-str (substring noise-sse--buffer event-start event-end)))
+        (setq noise-sse--buffer
+              (substring noise-sse--buffer (+ event-end 2)))
+        (when-let ((event (noise-sse--parse-event event-str)))
+          (noise-sse--handle-event event))))))
+
+(defun noise-sse--handle-event (event)
+  "Handle a parsed SSE EVENT.
+This function will be overridden in noise-receive to process envelopes."
+  (message "SSE event received: %s" event))
+
 (provide 'noise-sse)
 ;;; noise-sse.el ends here