refactor(ai_client): extract _send_cli_round_result helper (Phase 10 site 6)

Site L1990: inner _send(r_idx) in _send_gemini_cli had:
  try: resp_data = adapter.send(...)
  except Exception as e: events.emit('response_received', {'error': str(e)}); raise

This is Re-Raise Pattern 2 (catch + emit event + raise). Per TIER1_REVIEW,
the migration is to Result[T] because the audit does not yet recognize
events.emit as a structured error carrier.

New helper _send_cli_round_result(r_idx, adapter, payload, ...) -> Result[dict]:
- Emits request_start + [CLI] comms before SDK call
- Returns Result(data=resp_data) on SDK success
- On failure: emits response_received error event + returns Result(errors=[ErrorInfo(original=e)])

Inner _send refactored:
  send_result = _send_cli_round_result(r_idx, adapter, payload, ...)
  if not send_result.ok:
      raise cast(Exception, send_result.errors[0].original)
  resp_data = send_result.data

This preserves the original re-raise behavior so the outer
_send_gemini_cli try/except still catches and converts to Result.

Audit: ai_client BC 4 -> 3.

src/ai_client.py

@@ -1704,6 +1704,28 @@ def _create_gemini_cache_result(sys_instr: str, tools_decl: Any, file_items: lis
    errors=[ErrorInfo(kind=ErrorKind.INTERNAL, message=f"failed to create gemini cache: {type(e).__name__}: {e}", source="ai_client._create_gemini_cache_result", original=e)],
   )
 
+def _send_cli_round_result(r_idx: int, adapter: Any, payload: Any, safety_settings: list[Any], sys_instr: str, stream_callback: Optional[Callable[[str], None]]) -> Result[dict[str, Any]]:
+ """Call the Gemini CLI adapter for one round. Returns Result[resp_data].
+
+ On SDK failure, emits a response_received event with the error info
+ (preserving the original side-effect semantics) and returns
+ Result(errors=[ErrorInfo]). The caller (_send in _send_gemini_cli)
+ re-raises the original exception to preserve the outer catch flow.
+ """
+ events.emit("request_start", payload={"provider": "gemini_cli", "model": _model, "round": r_idx})
+ if r_idx > 0:
+  _append_comms("OUT", "request", {"message": f"[CLI] [round {r_idx}] [msg {len(payload)}]"})
+ send_payload: Any = json.dumps(payload) if isinstance(payload, list) else payload
+ try:
+  resp_data = adapter.send(cast(str, send_payload), safety_settings=safety_settings, system_instruction=sys_instr, model=_model, stream_callback=stream_callback)
+  return Result(data=resp_data)
+ except Exception as e:
+  events.emit("response_received", payload={"provider": "gemini_cli", "model": _model, "usage": {}, "latency": 0, "round": r_idx, "error": str(e)})
+  return Result(
+   data=None,
+   errors=[ErrorInfo(kind=ErrorKind.INTERNAL, message=str(e), source="ai_client._send_cli_round_result", original=e)],
+  )
+
 def _extract_gemini_thoughts(resp: Any) -> str:
  """
   Extracts concatenated thinking text from a Gemini response object's parts.
@@ -1981,15 +2003,10 @@ def _send_gemini_cli(md_content: str, user_message: str, base_dir: str,
   def _send(r_idx: int) -> NormalizedResponse:
    if adapter is None:
     return NormalizedResponse(text="(adapter unavailable)", tool_calls=[], usage_input_tokens=0, usage_output_tokens=0, usage_cache_read_tokens=0, usage_cache_creation_tokens=0, raw_response=None)
-   events.emit("request_start", payload={"provider": "gemini_cli", "model": _model, "round": r_idx})
-   if r_idx > 0:
-    _append_comms("OUT", "request", {"message": f"[CLI] [round {r_idx}] [msg {len(payload)}]"})
-   send_payload: Any = json.dumps(payload) if isinstance(payload, list) else payload
-   try:
-    resp_data = adapter.send(cast(str, send_payload), safety_settings=safety_settings, system_instruction=sys_instr, model=_model, stream_callback=stream_callback)
-   except Exception as e:
-    events.emit("response_received", payload={"provider": "gemini_cli", "model": _model, "usage": {}, "latency": 0, "round": r_idx, "error": str(e)})
-    raise
+   send_result = _send_cli_round_result(r_idx, adapter, payload, safety_settings, sys_instr, stream_callback)
+   if not send_result.ok:
+    raise cast(Exception, send_result.errors[0].original)
+   resp_data = send_result.data
    cli_stderr = resp_data.get("stderr", "")
    if cli_stderr:
     sys.stderr.write(f"\n--- Gemini CLI stderr ---\n{cli_stderr}\n-------------------------\n")

tests/tier2/phase10_site6_test.py

@@ -0,0 +1,27 @@
+"""Phase 10 site 6: _send_cli_round_result helper.
+
+Site L1990 (in _send_gemini_cli):
+  try: resp_data = adapter.send(...)
+  except Exception as e: events.emit('response_received', {'error': str(e)}); raise
+
+Re-Raise Pattern 2 (catch + emit + raise). Migration: extract Result helper.
+The inner _send calls the helper; on error, re-raise original exception
+(preserving outer _send_gemini_cli catch behavior).
+"""
+import sys
+sys.path.insert(0, ".")
+
+
+def test_phase10_site6_send_cli_round_result_exists():
+    import src.ai_client
+    assert hasattr(src.ai_client, "_send_cli_round_result"), \
+        "_send_cli_round_result helper missing"
+
+
+def test_phase10_site6_send_cli_round_result_returns_result():
+    import src.ai_client
+    import inspect
+    fn = src.ai_client._send_cli_round_result
+    sig = inspect.signature(fn)
+    assert "Result" in str(sig.return_annotation), \
+        f"_send_cli_round_result return must be Result, got {sig.return_annotation}"