feat: add opt-in cross-source hedged requests for chat

src/polygateway/client.py

@@ -19,7 +19,7 @@ from typing import TYPE_CHECKING, Any, Literal
 from polygateway.backends.memory.breaker import InMemoryGate
 from polygateway.backends.memory.cache import InMemoryCache
 from polygateway.backends.memory.limiter import InMemoryLimiter
-from polygateway.config import GatewaySettings
+from polygateway.config import GatewaySettings, check_hedge_assembly
 from polygateway.deadline import ensure_call_deadline, with_call_deadline
 from polygateway.errors import PolyGatewayError
 from polygateway.middleware.base import compose
@@ -237,6 +237,8 @@ class GatewayClient:
         structured_escalation: StructuredOutputStrategy | None = None,
         structured_max_retries: int = 1,
         call_deadline_s: float | None = None,
+        hedge_after_s: float | None = None,
+        hedge_max_extra: int = 1,
         now: Any = time.monotonic,
         sleep: Any = asyncio.sleep,
         rng: Any = random.random,
@@ -245,6 +247,15 @@ class GatewayClient:
         self._call_deadline_s = ensure_call_deadline(
             call_deadline_s, "GatewayClient(call_deadline_s=...)"
         )
+        # 对冲守卫与 GatewaySettings 共用同一份(issue #24 H4): 直接构造这条路
+        # 不经过 settings,值域/交叉守卫若只挂在 settings 上就会被它绕过
+        self._hedge_after_s = check_hedge_assembly(
+            hedge_after_s=hedge_after_s,
+            hedge_max_extra=hedge_max_extra,
+            sources=sources,
+            call_deadline_s=self._call_deadline_s,
+            origin="GatewayClient(hedge_after_s=...)",
+        )
         emitter = (
             TelemetryEmitter(telemetry, scope=scope, pricing=pricing, text_cap=text_cap)
             if telemetry is not None
@@ -267,6 +278,8 @@ class GatewayClient:
                 ceiling=float(max([64, *(s.max_concurrency for s in sources if s.max_concurrency)]))
             ),
             emitter=emitter,
+            # max_extra 不下传(issue #24 H5): v1 编排固定单路对冲,无消费者
+            hedge_after_s=self._hedge_after_s,
             now=now,
             sleep=sleep,
             rng=rng,
@@ -509,6 +522,8 @@ class GatewayClient:
             structured_escalation=escalation,
             structured_max_retries=settings.structured_max_retries,
             call_deadline_s=settings.call_deadline_s,
+            hedge_after_s=settings.hedge_after_s,
+            hedge_max_extra=settings.hedge_max_extra,
         )
         _mark_owned_components(client, limiter=limiter, breaker=breaker, telemetry=telemetry)
         client._owns_cache = cache is None  # 缓存后端可以是 None(backend=none),helper 会跳过