dsh-nl-model-switch: Switch DSH session models with a single sentence in the conversation.

# Introduction In DSH, switching models is done natively by typing `/model` and selecting from a popup. While this workflow is acceptable on desktop, it interrupts the flow in two scenarios: first, when you chat with the model via an IM bot on your mobile device, you lack a panel to click on; second, when you are in the middle of a discussion and want to hand off the remaining task to another model without leaving the chat interface. `dsh-nl-model-switch` fills this gap: simply say "switch to deepseek-v4-flash" in the chat, and the current session's model switches immediately, preserving the context so the new model continues processing your previous request. # What is this `dsh-nl-model-switch` is a DSH host plugin created by passi.