Model-Specific Spending Limits

Model-Specific Spending Limits

Provide the ability to set separate spending limits for individual models, alongside an overall account budget. For example, an organization could limit Opus to $100/month, Luna to $300/month, while maintaining a total budget cap of $500/month. This would provide better cost control while still allowing access to premium models when needed.

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| Field | Value |
| --- | --- |
| App version | 1.1.8 |
| OS | Windows 10.0.26100 |
| Theme | Rainglow Codecourse |
| Path | /chat |
| Tenure | Week 9 |

该 issue 未指定文件、测试或入口点。首先定位现有的 account-budget 和 model-selection 流程，然后确定如何测量使用量以及在哪里强制执行限制。完成后应包括为每个模型设置独立的月度限制，同时保留账户总体上限，并通过测试覆盖这两种限制。

由索引模型根据 Issue 内容生成。