[tests] add client-sdk pytests & delete client.py (#638)

# What does this PR do?

**Why**
- Clean up examples which we will not maintain; reduce the surface area
to the minimal showcases

**What**
- Delete `client.py` in /apis/*
- Move all scripts to unit tests
  - SDK sync in the future will just require running pytests

**Side notes**
- `bwrap` not available on Mac so code_interpreter will not work

## Test Plan

```
LLAMA_STACK_BASE_URL=http://localhost:5000 pytest -v ./tests/client-sdk
```
<img width="725" alt="image"
src="https://github.com/user-attachments/assets/36bfe537-628d-43c3-8479-dcfcfe2e4035"
/>


## Sources

Please link relevant resources if necessary.


## Before submitting

- [ ] This PR fixes a typo or improves the docs (you can dismiss the
other checks if that's the case).
- [ ] Ran pre-commit to handle lint / formatting issues.
- [ ] Read the [contributor
guideline](https://github.com/meta-llama/llama-stack/blob/main/CONTRIBUTING.md),
      Pull Request section?
- [ ] Updated relevant documentation.
- [ ] Wrote necessary unit or integration tests.

llama_stack/apis/models/client.py

@@ -1,92 +0,0 @@
-# Copyright (c) Meta Platforms, Inc. and affiliates.
-# All rights reserved.
-#
-# This source code is licensed under the terms described in the LICENSE file in
-# the root directory of this source tree.
-
-import asyncio
-import json
-
-from typing import List, Optional
-
-import fire
-import httpx
-from termcolor import cprint
-
-from .models import *  # noqa: F403
-
-
-class ModelsClient(Models):
-    def __init__(self, base_url: str):
-        self.base_url = base_url
-
-    async def initialize(self) -> None:
-        pass
-
-    async def shutdown(self) -> None:
-        pass
-
-    async def list_models(self) -> List[Model]:
-        async with httpx.AsyncClient() as client:
-            response = await client.get(
-                f"{self.base_url}/models/list",
-                headers={"Content-Type": "application/json"},
-            )
-            response.raise_for_status()
-            return [Model(**x) for x in response.json()]
-
-    async def register_model(self, model: Model) -> None:
-        async with httpx.AsyncClient() as client:
-            response = await client.post(
-                f"{self.base_url}/models/register",
-                json={
-                    "model": json.loads(model.model_dump_json()),
-                },
-                headers={"Content-Type": "application/json"},
-            )
-            response.raise_for_status()
-
-    async def get_model(self, identifier: str) -> Optional[Model]:
-        async with httpx.AsyncClient() as client:
-            response = await client.get(
-                f"{self.base_url}/models/get",
-                params={
-                    "identifier": identifier,
-                },
-                headers={"Content-Type": "application/json"},
-            )
-            response.raise_for_status()
-            j = response.json()
-            if j is None:
-                return None
-            return Model(**j)
-
-    async def unregister_model(self, model_id: str) -> None:
-        async with httpx.AsyncClient() as client:
-            response = await client.delete(
-                f"{self.base_url}/models/delete",
-                params={"model_id": model_id},
-                headers={"Content-Type": "application/json"},
-            )
-            response.raise_for_status()
-
-
-async def run_main(host: str, port: int, stream: bool):
-    client = ModelsClient(f"http://{host}:{port}")
-
-    response = await client.list_models()
-    cprint(f"list_models response={response}", "green")
-
-    response = await client.get_model("Llama3.1-8B-Instruct")
-    cprint(f"get_model response={response}", "blue")
-
-    response = await client.get_model("Llama-Guard-3-1B")
-    cprint(f"get_model response={response}", "red")
-
-
-def main(host: str, port: int, stream: bool = True):
-    asyncio.run(run_main(host, port, stream))
-
-
-if __name__ == "__main__":
-    fire.Fire(main)