Proposal: update the existing Qwen provider to QwenCloud branding and current official links

**例行检查**

[//]: # '方框内填 x 表示打钩'

- [x] 我已确认目前没有类似 features
- [ ] 我已确认我已升级到最新版本（本请求是 Provider 元数据与品牌兼容方案，不依赖用户安装版本）
- [x] 我已完整查看过项目 README，已确定现有版本无法满足需求
- [x] 我理解并愿意跟进此 features，协助测试和提供反馈
- [x] 我理解并认可上述内容，并理解项目维护者精力有限，**不遵循规则的 features 可能会被无视或直接关闭**

**功能描述**

FastGPT already has a Qwen provider and broad model coverage. Please confirm whether the existing provider should update its user-facing branding, official links, endpoints, and model-maintenance source to QwenCloud while preserving saved configuration IDs, or whether a separate QwenCloud preset is required for international endpoints and plans.

**应用场景**

International users need one current official path for the QwenCloud API key, models, documentation, and pricing without breaking existing FastGPT Qwen configurations. Direct QwenCloud calls and user-configured aggregation gateways should remain distinguishable.

**相关示例**

- Website: https://www.qwencloud.com/
- API keys: https://home.qwencloud.com/api-keys
- Developer docs: https://docs.qwencloud.com/developer-guides/getting-started/introduction
- Models: https://www.qwencloud.com/models
- Pricing: https://docs.qwencloud.com/developer-guides/getting-started/pricing

The QwenCloud team can provide approved copy, endpoint validation, recommended models, and test support after the preferred migration path is confirmed.

QwenCloud contact: Jialing / QwenCloud Product Manager / https://github.com/evelyn-jialin-zhang