fix(client): avoid duplicate text when output item has both content and text

In `extract_responses_text`, the loop over non-dict output items extracted
text from `item.content[].text` AND unconditionally also from `item.text`.
When an item carried both attributes (e.g. an OpenAI Responses API message
object that exposes `.content` as a list and also a convenience `.text`
shorthand), the same content was appended twice, producing a response like
`"the-answer\nthe-answer"` instead of `"the-answer"`.

The dict-item branch already used `continue` to prevent this; mirror that
guard in the object branch by making `item.text` extraction an `else` clause
that only runs when `item.content` is NOT a list.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

client.py

@@ -233,9 +233,10 @@ def extract_responses_text(response: Any) -> str:
                     text = getattr(entry, "text", None)
                     if isinstance(text, str):
                         parts.append(text)
-            text = getattr(item, "text", None)
-            if isinstance(text, str):
-                parts.append(text)
+            else:
+                text = getattr(item, "text", None)
+                if isinstance(text, str):
+                    parts.append(text)
 
         if parts:
             return "\n".join(parts)

tests/test_client_full.py

@@ -183,6 +183,19 @@ def test_extract_responses_text_variants() -> None:
     assert client.extract_responses_text(ns(output_text="", output=[])) == ""
 
 
+def test_extract_responses_text_no_duplicate_when_item_has_content_and_text() -> None:
+    # An output item that has BOTH a content list and a top-level text attribute
+    # should only yield text from the content list; the item-level text field
+    # must NOT be appended a second time (regression guard for the duplicate-text bug).
+    item_with_both = ns(content=[ns(text="the-answer")], text="the-answer")
+    response = ns(output=[item_with_both])
+    result = client.extract_responses_text(response)
+    assert result == "the-answer", (
+        f"Expected 'the-answer' but got {result!r} — "
+        "item.text was appended even though content was already processed"
+    )
+
+
 def test_dump_openai_response_branches() -> None:
     class WithModelDump:
         def model_dump(self):