fixup! feat(model-routing): MODEL_ALIASES and cross-provider rotation

Await _execute_streaming() in CrossProviderExecutor.execute() so callers
receive the async generator instead of an unawaited coroutine.

Fixes: #58

Author: b3nw

.fork/features/model-routing.md

@@ -0,0 +1,24 @@
+# model-routing — MODEL_ALIASES and Cross-Provider Rotation
+
+## 2026-06-23 — Fix streaming coroutine not awaited in CrossProviderExecutor
+
+Target: `feat(model-routing): MODEL_ALIASES and cross-provider rotation`
+Files:
+- `src/rotator_library/client/cross_provider_executor.py`
+
+Working commits before autosquash:
+- (see fixup commit hash after commit)
+
+Verification:
+- `uv run python3 -m py_compile src/rotator_library/client/cross_provider_executor.py` — passed
+- `uv run ruff check src/rotator_library/client/cross_provider_executor.py --select F401,F811,F821,E9` — passed
+
+Notes:
+- `CrossProviderExecutor.execute()` returned `self._execute_streaming(...)` without
+  `await`. Since `_execute_streaming` is `async def` (returns a coroutine wrapping the
+  inner `_stream_with_failover()` async generator), callers received a coroutine object
+  instead of the async generator. The Anthropic `/v1/messages` streaming wrapper then
+  failed with `'async for' requires an object with __aiter__ method, got coroutine`.
+- Fix: `return await self._execute_streaming(...)` so the coroutine resolves to the
+  inner async generator before being returned to the caller.
+- Ref: https://github.com/b3nw/LLM-API-Key-Proxy/issues/58

src/rotator_library/client/cross_provider_executor.py

@@ -82,7 +82,7 @@ async def execute(
         )
 
         if is_streaming:
-            return self._execute_streaming(
+            return await self._execute_streaming(
                 canonical_model, available_targets, retry_mode,
                 request, pre_request_callback, **kwargs,
             )