fix(llmcore): suppress intermediate error yield during retry and handle ChunkedEncodingError

When the LLM stream encounters a transient network error (ConnectionError,
Timeout, SSLError, ProxyError), the retry path yielded the error string
back to the caller on every attempt. This caused the UI to display a wall
of '!!!Error: ProxyError!!!Error: ConnectionError!!!Error: SSLError'
strings during a network blip, even when the retry ultimately succeeded.

Match the existing HTTP retry path (which sleeps without yielding) by
removing the intermediate yield so the caller only sees the final error
if retries are exhausted. Retry attempts remain visible via the existing
'[LLM Retry] ...' stdout log.

Also extend the exception tuple to include ChunkedEncodingError. Without
it, a truncated chunked response falls through to the bare 'except
Exception' branch and aborts the stream with no retry, even though the
transport-level error is transient and recoverable.

Closes #571

Author: Kailigithub

llmcore.py

@@ -386,13 +386,13 @@ def _delay(resp, attempt):
                 except StopIteration as e:
                     if not e.value and not streamed: raise requests.ConnectionError("empty response")
                     return e.value or []
-        except (requests.Timeout, requests.ConnectionError) as e:
+        except (requests.Timeout, requests.ConnectionError, requests.exceptions.ChunkedEncodingError) as e:
             #pathlib.Path(__file__).parent.joinpath('temp','bad_requests.json').write_text(json.dumps({"url":url,"headers":headers,"payload":payload,"err":str(e),"t":time.time()},ensure_ascii=False),encoding='utf-8')
             err = f"!!!Error: {type(e).__name__}: {e}" if str(e) else f"!!!Error: {type(e).__name__}"
             if attempt < sess.max_retries:
                 d = _delay(None, attempt)
                 print(f"[LLM Retry] {type(e).__name__}, retry in {d:.1f}s ({attempt+1}/{sess.max_retries+1})")
-                yield err; time.sleep(d); continue
+                time.sleep(d); continue
             yield err; return [{"type": "text", "text": err}]
         except Exception as e:
             err = f"\n\n[!!! 流异常中断 {type(e).__name__}: {e} !!!]" if streamed else f"!!!Error: {type(e).__name__}: {e}"