fix(webui): hide subagent backfill payloads

nanobot/webui/transcript.py

@@ -17,7 +17,8 @@ from urllib.parse import unquote, urlparse
 from loguru import logger
 
 from nanobot.config.paths import get_webui_dir
-from nanobot.session.automation_turns import is_automation_history_message, is_automation_kind
+from nanobot.session.automation_turns import is_automation_kind
+from nanobot.session.history_visibility import is_hidden_history_message
 from nanobot.session.manager import SessionManager
 from nanobot.webui.metadata import WEBUI_MESSAGE_SOURCE_METADATA_KEY, WEBUI_TURN_METADATA_KEY
 
@@ -782,7 +783,7 @@ def write_session_messages_as_transcript(
     target_chat_id = _chat_id_from_session_key(target_key)
     rows: list[dict[str, Any]] = []
     for msg in messages:
-        if is_automation_history_message(msg):
+        if is_hidden_history_message(msg):
             continue
         role = msg.get("role")
         content = msg.get("content")
@@ -854,13 +855,28 @@ def build_user_transcript_event(
     return event
 
 
+def _is_legacy_raw_subagent_result(message: dict[str, Any]) -> bool:
+    content = message.get("content")
+    if not isinstance(content, str):
+        return False
+    text = content.replace("\r\n", "\n").strip()
+    return (
+        text.startswith("[Subagent '")
+        and "\n\nTask:" in text
+        and "\n\nResult:" in text
+        and "Summarize this naturally" in text
+    )
+
+
 def _session_user_event(
     session_key: str,
     message: dict[str, Any],
 ) -> dict[str, Any] | None:
     if message.get("role") != "user":
         return None
-    if is_automation_history_message(message):
+    if is_hidden_history_message(message):
+        return None
+    if _is_legacy_raw_subagent_result(message):
         return None
     content = message.get("content")
     text = content if isinstance(content, str) else ""