[Renderer] Remove InputPreprocessor

[DarkLight1337]

Purpose

Now that #28631 has been merged, we can remove support for unprocessed inputs to the AsyncLLM.

Test Plan

Test Result

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• The purpose of the PR, such as "Fix some issue (link existing issues this PR will resolve)".
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[gemini-code-assist]

Code Review

This pull request removes the InputPreprocessor and associated logic, transitioning the engine to strictly accept pre-processed EngineInput instead of raw PromptType or EngineCoreRequest. It also removes tokenization_kwargs from several core method signatures across protocol.py, async_llm.py, and input_processor.py. Review feedback identifies that the encode method signatures in both the protocol and AsyncLLM were missed during this refactor and still include the deprecated PromptType. Additionally, an internal call within _add_streaming_input_request needs to be updated to provide a valid EngineInput dictionary to avoid runtime errors.

[mergify]

Hi @DarkLight1337, the pre-commit checks have failed. Please run:

uv pip install pre-commit>=4.5.1
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pre-commit run --all-files

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Tip

Is mypy failing?

mypy is run differently in CI. If the failure is related to this check, please use the following command to run it locally:

# For mypy (substitute "3.10" with the failing version if needed)
pre-commit run --hook-stage manual mypy-3.10

[mergify]

Hi @DarkLight1337, the pre-commit checks have failed. Please run:

uv pip install pre-commit>=4.5.1
pre-commit install
pre-commit run --all-files

Then, commit the changes and push to your branch.

For future commits, pre-commit will run automatically on changed files before each commit.

Tip

Is mypy failing?

mypy is run differently in CI. If the failure is related to this check, please use the following command to run it locally:

# For mypy (substitute "3.10" with the failing version if needed)
pre-commit run --hook-stage manual mypy-3.10