dsh-lens: Get diagnostics while coding in DeepSeek Harness

# Introduction When using DSH (DeepSeek Harness) as a coding agent, a common pain point arises: after the model performs `write` / `edit` / `bash`, determining whether the generated code contains type errors or violates lint rules requires you to run the toolchain yourself. The later the problem is discovered, the higher the repair cost. In the Pi host, pi-lens has already solved this: the engine runs LSP, linters, formatters, type checkers, and structural analysis while the agent is writing code. dsh-lens simply connects the same engine to DSH. Below is an introduction to its positioning, capabilities, installation, and configuration. # What is dsh-lens dsh-lens is pi-lens for DSH.