feat: add qwen3.5 flash model template

[luobily]

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ChangeLog

Language	Changelog
🇺🇸 English	Add qwen3.5 flash model template
🇨🇳 中文	新增 qwen3.5 flash 模版

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 15.84%. Comparing base (705dd82) to head (dc74b8b).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6787      +/-   ##
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+ Coverage   15.82%   15.84%   +0.01%     
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  Files        3998     3998              
  Lines      328179   328128      -51     
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+ Hits        51933    51983      +50     
+ Misses     270350   270244     -106     
- Partials     5896     5901       +5     

Flag	Coverage Δ
by-github-actions	15.84% <ø> (+0.01%)	⬆️

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[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Preserve thinking-mode completion pricing

When clients use qwen-plus with thinking enabled, this flat completion rate is what token usage aggregation reads (internal/apps/ai-proxy/handlers/handler_token_usage/aggregate.go:203-204) and applies to all output tokens (aggregate.go:177-178). The official Aliyun pricing table for qwen-plus still lists 2 CNY/M for non-thinking output but 8 CNY/M for thinking output in the ≤128K tier (https://help.aliyun.com/zh/model-studio/model-pricing), while this template still advertises enable_thinking; lowering the rate to 0.000002 will under-report/under-charge thinking calls by 4x. Keep the thinking-mode rate or add mode-specific pricing before changing this value.

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