Localize zh-CN model preset feedback

[w287346141]

Summary

• localize zh-CN /model feedback label from model to 模型
• localize zh-CN /preset feedback label from preset to 预设
• show full DeepSeek V4 model IDs in zh-CN preset feedback for consistency with /model
• add coverage to prevent the labels from regressing

Verification

• npm.cmd run test -- carbon-productization.test.ts
• npm.cmd run typecheck
• npm.cmd run verify

[w287346141]

Superseded by #20, which batches this zh-CN model/preset localization together with #14 and resolves the shared tests/carbon-productization.test.ts conflict ahead of review.