[Misc] Bump ray to 2.48.0

[ruisearch42]

Essential Elements of an Effective PR Description Checklist

• The purpose of the PR, such as "Fix some issue (link existing issues this PR will resolve)".
• The test plan, such as providing test command.
• The test results, such as pasting the results comparison before and after, or e2e results
• (Optional) The necessary documentation update, such as updating supported_models.md and examples for a new model.

Purpose

Higher ray version is required for ray.experimental.channel.accelerator_context module.

Fixes the following issue:

[2025-08-02T07:50:37Z] (EngineCore_0 pid=7101)   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/executor/ray_distributed_executor.py", line 77, in execute_model
[2025-08-02T07:50:37Z] (EngineCore_0 pid=7101)     self.forward_dag = self._compiled_ray_dag(enable_asyncio=False)
[2025-08-02T07:50:37Z] (EngineCore_0 pid=7101)                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[2025-08-02T07:50:37Z] (EngineCore_0 pid=7101)   File "/usr/local/lib/python3.12/dist-packages/vllm/executor/ray_distributed_executor.py", line 612, in _compiled_ray_dag
[2025-08-02T07:50:37Z] (EngineCore_0 pid=7101)     from ray.experimental.channel.accelerator_context import (
[2025-08-02T07:50:37Z] (EngineCore_0 pid=7101) ModuleNotFoundError: No module named 'ray.experimental.channel.accelerator_context'

Test Plan

Test Result

(Optional) Documentation Update

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[gemini-code-assist]

Code Review

This pull request bumps the ray dependency to version 2.48.0 to resolve a ModuleNotFoundError. The change is straightforward and affects the requirements files. My main concern is the lack of a test plan and results in the pull request description. Given that ray is a core dependency, it's crucial to verify that this version bump does not introduce any regressions. I've left a comment requesting the author to provide testing evidence.

[gemini-code-assist]

Bumping the ray version to 2.48.0 is well-justified to resolve the ModuleNotFoundError.

However, ray is a critical dependency for distributed execution, and version bumps can introduce subtle regressions or performance changes. The pull request description is missing a Test Plan and Test Results, which are essential for a change like this.

To ensure the stability and performance of the project, please:

1. Run the full test suite, paying close attention to distributed tests that use the ray backend.
2. Update the pull request description with the test plan and a summary of the results, confirming that all tests pass and there are no performance regressions.

Without this validation, we risk merging a change that could break key functionalities.