feat: add Qwen3.6 MoE model support

[qinyiqun]

Summary

Motivation

Closes #

Type of Change

• feat — new feature / new model
• fix — bug fix
• perf — performance improvement (no behavioral change)
• refactor — code restructuring without behavior change
• test — adding or fixing tests only
• docs — documentation only
• build / ci — build system or CI configuration
• chore — tooling, formatting, or other non-code changes
• Breaking change

Test Results of Involved Models on Supported Platforms (Please attach screenshots)

Benchmark / Performance Impact

Notes for Reviewers

CI / ChatOps

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[PanZezhong1725]

qwen3.5模型的特殊点不应以has_mamba_state做判断依据

[qinyiqun]

我还在看代码，先不急审核

[wooway777]

我还在看代码，先不急审核

那你早晨还专门跟我说rebase完了···

[pengcheng888]

这个是检查config.json中的值的函数，被qwen3_next和3_5掉用的，放在这个位置不好吧。

感觉不能属于这个config文件夹中。

[qinyiqun]

这个config应该可以算是一个通用的config，供所有类似架构的模型使用，放在这里应该并无不妥