dsh-anal-gland: Anal Gland Care Tool

The `dsh-anal-gland` in DeepSeek Harness (DSH) is an anal gland care plugin maintained by uckkk. Implemented in pure Node.js, it relies on no network requests and focuses on providing users with anal gland care advice. The installation command is `dsh plugin add github:uckkk/dsh-anal-gland`, after which its `anal_gland` tool can be invoked within a session. Because it has no network dependencies, it is suitable for offline environments and runs with the permissions of the current DSH process.