Create a profile field or "announcement" for new job attributable to brigade

Many members end up in new jobs because of their involvement with the brigade, we should provide a way for members to share when that happens (or that it already happened). This could create a badge in someone's profile, add them to some sort of wall, and give the brigade much-needed metrics on ROI for sponsors

该 issue 未确定任何文件、测试或实现入口。首先明确该功能是个人资料字段、公告墙、徽章、赞助商指标，还是它们的某种组合；应通过达成一致的设计和可衡量的 ROI 报告行为来定义“done”。

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