Clickable AI credit usage percentage for detailed consumption breakdown

### Feature summary

Provide a detailed, itemized breakdown of AI credit consumption when a user interacts with the usage percentage indicator in the Accounts settings UI.

### What problem are you trying to solve?

Currently, in the Accounts / Usage & Plan settings

the "AI credits (resets monthly)" section displays a percentage indicator (e.g., "0.5%") but offers no visibility into how those credits were expended.

As a user, I can see that my credits are being consumed, but I have a blind spot regarding which specific repositories, projects, or interactions are driving that consumption. This lack of telemetry makes it difficult to audit usage, manage token consumption efficiently, or project future plan needs.

### Proposed solution

Make the AI credit usage percentage element [as highlighted in red box

] a clickable interactive target. Clicking this element should surface a modal or navigate to a detailed view displaying an itemized history of credit consumption.

This detailed listing should include:

What: The repository, project, or model context that triggered the consumption.

When: A precise timestamp for the activity.

Amount: The number of credits or specific token breakdown used for that request.

### Workflow impact

This change would significantly improve the transparency of the GitHub App ecosystem. Users will be able to self-audit their resource consumption directly from their profile without guessing which workflows are the most resource-intensive. It transforms a static metric into an actionable, analytical tool for managing developer resources.

### Installation context

_No response_

### Additional context

_No response_

从 Accounts / Usage & Plan 设置 UI 开始，找到 AI credits 百分比指示器。确定其使用数据当前是如何获取的，然后定义可点击的详细视图，使其显示每项活动对应的 repository、project 或 model 上下文、时间戳以及 credit 或 token 数量。

由索引模型根据 Issue 内容生成。