fix(chat): preserve plain-turn matching during settlement

Keep whitespace-normalized text matches for plain Agent rows, retain float timestamps for Gateway turn checkpoints, and test optional attachment suffix behavior rather than source spelling.

Assisted-by: Hermes Agent:gpt-6-sol
Assisted-by: Codex:gpt-6-luna

api/gateway_chat.py

@@ -1297,7 +1297,11 @@ def _run_gateway_chat_streaming(
             # role/content ordering instead of turn order.
             assistant_ts = now + 0.000001
             pending_source = getattr(s, "pending_user_source", None) or "webui"
-            from api.streaming import _active_turn_authority, _materialize_active_turn_user
+            from api.streaming import (
+                _active_turn_authority,
+                _active_turn_token_matches,
+                _materialize_active_turn_user,
+            )
 
             active_turn_identity = _active_turn_authority(s, stream_id, msg_text)
             user_msg = _materialize_active_turn_user(
@@ -1373,6 +1377,14 @@ def _run_gateway_chat_streaming(
                         if latest_text == msg_norm:
                             display = display[:-1]
                 s.messages = display + [user_msg, assistant_msg]
+            if active_turn_identity.get("token"):
+                current_display_rows = [
+                    message
+                    for message in s.messages
+                    if _active_turn_token_matches(message, active_turn_identity)
+                ]
+                if len(current_display_rows) == 1:
+                    current_display_rows[0]["timestamp"] = user_msg["timestamp"]
             s.active_stream_id = None
             s.pending_user_message = None
             s.pending_attachments = None

api/streaming.py

@@ -2105,6 +2105,11 @@ def _active_turn_user_text_matches(message, expected_text):
         actual_text = content
     else:
         return False
+    if (
+        isinstance(content, str)
+        and " ".join(actual_text.split()) == " ".join(expected_text.split())
+    ):
+        return True
     return _submitted_user_text_matches(actual_text, expected_text)
 
 

tests/test_batch_fixes.py

@@ -41,12 +41,13 @@ class TestRootWorkspaceUnblocked:
         assert "'/etc'" in src or 'Path("/etc")' in src or "Path('/etc')" in src
         assert "'/proc'" in src or 'Path("/proc")' in src or "Path('/proc')" in src
 
-    def test_split_guard_present(self):
-        src = read("api/streaming.py")
-        assert "'\\n\\n[Attached files:' in msg_text" in src, (
-            "base_text split must guard against missing '[Attached files:' "
-            "to avoid empty-string on plain messages"
-        )
+    def test_attached_files_suffix_is_optional(self):
+        from api.models import _strip_attached_files_marker
+
+        assert _strip_attached_files_marker("Plain message") == "Plain message"
+        assert _strip_attached_files_marker(
+            "Question\n\n[Attached files: photo.png]"
+        ) == "Question"
 
 
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