Shared response buffer backend

sia/response_buffer.py

@@ -0,0 +1,26 @@
+class ResponseBuffer:
+    def __init__(self):
+        self._text = ""
+        self._observers = []
+    
+    def add_observer(self, callback):
+        self._observers.append(callback)
+    
+    def get_text(self):
+        return self._text
+    
+    def append_text(self, text):
+        self._text += text
+        self._notify_observers()
+    
+    def set_text(self, text):
+        self._text = text
+        self._notify_observers()
+    
+    def clear(self):
+        self._text = ""
+        self._notify_observers()
+    
+    def _notify_observers(self):
+        for observer in self._observers:
+            observer(self._text)