[remove import *][2/n] remove rest of import * in implementations (#690)

# What does this PR do?

- see https://github.com/meta-llama/llama-stack/pull/689
<img width="591" alt="image"
src="https://github.com/user-attachments/assets/76946a67-7373-43b5-8a03-0ad201aa543b"
/>

- leaving `tools/builtin.py` to avoid conflicts


## Test Plan

- see https://github.com/meta-llama/llama-stack/pull/689

## 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/providers/remote/agents/sample/sample.py

@@ -4,12 +4,10 @@
 # This source code is licensed under the terms described in the LICENSE file in
 # the root directory of this source tree.
 
+from llama_stack.apis.agents import Agents
 from .config import SampleConfig
 
 
-from llama_stack.apis.agents import *  # noqa: F403
-
-
 class SampleAgentsImpl(Agents):
     def __init__(self, config: SampleConfig):
         self.config = config