feat: support training with JSON string tool arguments (#3136)

* feat: support training with JSON string tool arguments; fix PyArrow data type inconsistent error

* feat: raise error for tool call arguments decode

* Add test_chat_templates_tool_call_string_arguments.py

Add test for string arguments

* fix: change to correct qwen3 tokenizer

* fix: update docs to clarify arguments json

* chore: lint

* fix: duplicate

* chore: revert

* feat: add error to faq

* fix: remove duplicate fixture

---------

Co-authored-by: caoqinping <caoqinping@lixiang.com>
Co-authored-by: gamersover-blog <1611885128@qq.com>
Co-authored-by: NanoCode012 <nano@axolotl.ai>

docs/dataset-formats/conversation.qmd

@@ -212,6 +212,14 @@ Instead of passing `tools` via the system prompt, an alternative method would be
 Tools need to follow [JSON schema](https://json-schema.org/learn/getting-started-step-by-step).
 :::
 
+::: {.callout-warning}
+If you have tool arguments with same name but different dtypes (like `"time": string` and `"time": number`), please save `arguments: ` as JSON string to prevent `datasets` from having casting issues.
+
+```
+"arguments": "{\"...\": \"...\"}"
+```
+:::
+
 Example config for Llama4:
 ```yaml
 chat_template: llama4