Add chat support for invisible interface in Bluesky buffers

ChatBuffer now has get_message(), get_formatted_message(), and view_item()
so repeat_item, copy_to_clipboard, and view work correctly with chat
messages. open_conversation (Ctrl+Win+Alt+C) detects chat buffers and
delegates to view_chat(). Opening a chat buffer now announces its name
and item count for screen reader feedback.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/controller/blueski/handler.py

@@ -554,6 +554,10 @@ class Handler:
 
     def open_conversation(self, controller, buffer):
         """Standard action for Control+Win+C"""
+        # If this is a chat conversation list, open the selected chat
+        if buffer.type == "chat" and hasattr(buffer, "view_chat"):
+            buffer.view_chat()
+            return
         item = buffer.get_item()
         if not item:
             return

src/controller/buffers/blueski/chat.py

@@ -369,10 +369,21 @@ class ConversationListBuffer(BaseBuffer):
             start=True
         )
 
-        # Navigate to the newly created buffer
+        # Navigate to the newly created buffer and announce it
         new_index = controller.view.search(title, account_name)
         if new_index is not None:
             controller.view.change_buffer(new_index)
+            buffer_obj = controller.search_buffer(title, account_name)
+            if buffer_obj and hasattr(buffer_obj.buffer, "list"):
+                try:
+                    count = buffer_obj.buffer.list.get_count()
+                    if count > 0:
+                        msg = _("{0}, {1} of {2}").format(title, buffer_obj.buffer.list.get_selected()+1, count)
+                    else:
+                        msg = _("{0}. Empty").format(title)
+                except Exception:
+                    msg = _("{0}. Empty").format(title)
+                output.speak(msg, True)
 
     def destroy_status(self):
         pass
@@ -460,6 +471,40 @@ class ChatBuffer(BaseBuffer):
         """Global shortcut for DM."""
         self.on_reply(None)
 
+    def get_message(self):
+        """Return a readable summary for the selected chat message."""
+        item = self.get_item()
+        if item is None:
+            return None
+        composed = self.compose_function(
+            item, self.session.db, self.session.settings,
+            self.session.settings["general"].get("relative_times", False),
+            self.session.settings["general"].get("show_screen_names", False),
+        )
+        return " ".join(composed)
+
+    def get_formatted_message(self):
+        """Return the text content of the selected chat message."""
+        item = self.get_item()
+        if item is None:
+            return None
+        composed = self.compose_function(
+            item, self.session.db, self.session.settings,
+            self.session.settings["general"].get("relative_times", False),
+            self.session.settings["general"].get("show_screen_names", False),
+        )
+        return composed[1]
+
+    def view_item(self, item=None):
+        """View the selected chat message in a dialog."""
+        msg = self.get_formatted_message()
+        if not msg:
+            output.speak(_("No message selected."), True)
+            return
+        viewer = blueski_messages.text(title=_("Chat message"), text=msg)
+        viewer.message.ShowModal()
+        viewer.message.Destroy()
+
     def remove_buffer(self, force=False):
         """Allow removing this buffer."""
         from wxUI import commonMessageDialogs