dsh-date-format: Date Formatting Plugin

`dsh-date-format` is a pure Node date formatting plugin for DeepSeek Harness (DSH), maintained by developer `uckkk`. It addresses the issue of DSH relying on external tools or regular expressions for time-related logic, supports localized date processing without network requests, and is well suited for offline scenarios. The plugin depends on `@deepseek-ai/cordis` and `@deepseek-ai/dsh-tools`; once installed, it can be called within a session to quickly generate date strings in specific formats. Users should check environment dependencies and review the source code before use to ensure safety.