fix: embed() sends string input instead of array, breaking OpenAI-compatible providers (#586)

* fix: wrap single embed() input in array for OpenAI-compatible provider compatibility

* Fix input format in embedding test assertion

src/embedding_client.py

@@ -99,7 +99,7 @@ class _EmbeddingClient:
             return self._validate_embedding_dimensions(response.embeddings[0].values)
         else:  # openai
             response = await self.client.embeddings.create(
-                model=self.model, input=query
+                model=self.model, input=[query]
             )
             return self._validate_embedding_dimensions(response.data[0].embedding)
 

tests/llm/test_embedding_client.py

@@ -51,7 +51,7 @@ async def test_openai_embedding_client_uses_configured_model_and_dimensions(
 
     assert embedding == [0.1] * 8
     assert fake_embeddings.calls == [
-        {"model": "text-embedding-3-small", "input": "hello world"}
+        {"model": "text-embedding-3-small", "input": ["hello world"]}
     ]