dsh-quit-idle-fix: Fix false alarm of interruption during DSH desktop idle exit

`dsh-quit-idle-fix` is a DSH client plugin (version 0.1.0, MIT) maintained by shuaichewang. It fixes interrupt false positives when exiting the desktop: pure prompt messages delivered via `agent.inject()` in idle sessions remain in the `next-step` queue and are mistakenly treated as active tasks by the exit checks. The plugin only clears notifications of four types—`user-approval`, `working-directory`, `cordis-host-runner`, and `plan-mode`—when the agent is idle, and does not interfere with running agents, user turns, jobs, or scheduled tasks.