[Renderer] Separate out RendererConfig from ModelConfig

[DarkLight1337]

Purpose

Move out renderer-specific fields into a new config.

• ModelConfig.tokenizer -> RendererConfig.tokenizer
• ModelConfig.tokenizer_mode -> RendererConfig.tokenizer_mode
• ModelConfig.tokenizer_revision -> RendererConfig.tokenizer_revision
• ModelConfig.skip_tokenizer_init -> RendererConfig.skip_tokenizer_init
• ModelConfig.io_processor_plugin -> RendererConfig.io_processor_plugin
• MultiModalConfig.media_io_kwargs -> RendererConfig.media_io_kwargs
• ModelConfig.allowed_local_media_path -> RendererConfig.allowed_local_media_path
• ModelConfig.allowed_media_domains -> RendererConfig.allowed_media_domains

Since renderer may still need to access model config fields (like hf_config), RendererConfig contains ModelConfig. This also means a bunch of tests need to be updated to pass RendererConfig(model_config=model_config) explicitly to VllmConfig.

Related changes:

• Separate ModelConfig.maybe_pull_model_tokenizer_for_runai into ModelConfig.maybe_pull_model_for_runai and RendererConfig.maybe_pull_tokenizer_for_runai. Also fix the latter using model instead of tokenizer.
• Refactor ModelConfig.get_and_verify_max_len into ModelConfig.recalculate_max_model_len and call it twice during initialization: inside ModelConfig.__post_init__ without tokenizer, and after RendererConfig is constructed with the tokenizer.
• Update tokenizer/processor factories and chat utils to accept renderer_config instead of model_config.
• Update multimodal registry and budget to accept renderer_config instead of model_config.
• Update SupportsTranscription interface methods to accept renderer_config instead of model_config.
• Add _HfExamplesInfo.build_model_config and _HfExamplesInfo.build_renderer_config convenience methods for testing.

Prepare for #22880

Test Plan

Test Result

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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.
• (Optional) Release notes update. If your change is user facing, please update the release notes draft in the Google Doc.

[mergify]

Documentation preview: https://vllm--30145.org.readthedocs.build/en/30145/

[DarkLight1337]

Force-merging as LoRA tests are timing out on main