DeepSeek streaming: HTTP client buffers full response body (missing stream option on Guzzle/Laravel HTTP)

[Jeo-Meek]

1. Phenomenon: When using DeepSeek::stream() / streaming chat/completions, the response body is buffered in its entirety on the PHP side, and while (! $response->getBody()->eof()) waits for the upstream to complete before continuing to read data; SSE cannot truly process data edge-to-edge.

2. Reason (brief description): Although 'stream' => true is present in the request JSON, Laravel HTTP / Guzzle does not have withOptions(['stream' => true]) set, resulting in non-streaming reading of the body.

3. Comparison: Providers such as OpenAI, Groq, Mistral, and Anthropic within the same warehouse have already written withOptions(['stream' => true]) before post, whereas DeepSeek (and optionally Perplexity HandlesHttpRequests) is inconsistent.

4. Suggested modification: In the sendRequest() method of src/Providers/DeepSeek/Handlers/Stream.php, add ->withOptions(['stream' => true]) to $this->client in a chained manner (consistent with Groq/Mistral, etc.).

5. Environment: prism-php/prism version number (e.g. v0.99.22), PHP version, Laravel version (optional).

6. Reproduction: The minimal reproduction can be described as "issuing a stream request with 'stream: true' to DeepSeek, and observing in the server logs or breakpoints whether 'read()' returns successively during the connection's lifetime" — or explaining that "in the Network, the upstream is chunked, but the PHP side fetches the complete body at once".