dsh-task-models: Enhanced DeepSeek Harness Subagent Model and Reasoning Effort Selection

The dsh-task-models plugin extends the native subagent tools in DeepSeek Harness (DSH), allowing you to specify a particular model and reasoning effort when invoking `subagent` and `subagent_fork`. By overriding the native tools to add `model` and `reasoning_effort` parameters, it supports both background sessions and one-shot foreground execution. In v0.2.0, the standalone `task` tool was removed and its functionality was merged into subagents. Note that this plugin is officially deprecated; you should confirm whether your current DSH version still requires it.