[trainer] feat: Specify apply_chat_template_kwargs from config

[HollowMan6]

What does this PR do?

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Now we support specifying apply_chat_template_kwargs from config

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API and Usage Example

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e.g. For #1711, now users can directly use

+data.apply_chat_template_kwargs.enable_thinking=False

to disable thinking mode in Qwen3, without the need to modify the code.

Design & Code Changes

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Users can pass and append anything to data.apply_chat_template_kwargs, and this will be passed when .apply_chat_template() is called.

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[gemini-code-assist]

Code Review

This pull request introduces a new configuration option, apply_chat_template_kwargs, allowing users to pass additional arguments to tokenizer.apply_chat_template without code modifications. The change is consistently applied across various dataset loading and processing scripts, as well as related configuration files. My review found one area for improvement in recipe/minicpmo/rl_dataset.py to enhance robustness against potential TypeError if a function is called with None arguments, for which I've provided a suggestion.