llm: add created/model fields, non-streaming support, and tests (#13660)

* llm: add created/model fields, non-streaming support, and tests

- Add `created` timestamp and `model` fields to response (required by OpenAI spec)
- Add non-streaming mode support for /v1/chat/completions
- Add `send_data` helper to HTTPRequestHandler for responses with Content-Length
- Refactor viz/serve.py to use send_data
- Add integration tests using real OpenAI client

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* add openai to testing

* toml

* Remove 'openai' from dependencies

Removed 'openai' from the dependencies list.

* bump cache

---------

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

pyproject.toml

@@ -69,17 +69,14 @@ testing_minimal = [
   "hypothesis",
   "z3-solver",
 ]
-testing_unit = ["tinygrad[testing_minimal]", "tqdm", "safetensors", "tabulate"]
+testing_unit = ["tinygrad[testing_minimal]", "tqdm", "safetensors", "tabulate", "openai"]
 testing = [
-  "tinygrad[testing_minimal]",
+  "tinygrad[testing_unit]",
   "pillow",
   "onnx==1.19.0",
   "onnx2torch",
   "onnxruntime",
   "opencv-python",
-  "tabulate",
-  "tqdm",
-  "safetensors",
   "transformers",
   "sentencepiece",
   "tiktoken",