Provides a global installation method via npm/pnpm

[linghengqian]

• Currently, https://github.com/deepseek-ai/deepseek-harness/blob/master/README.md#run-from-npm only mentions starting it via npx @deepseek-ai/dsh web. Due to pnpm's security mechanisms, the pnpm startup method is somewhat verbose.

pnpm dlx \
  --allow-build=@deepseek-ai/dsh-subprocess-local \
  --allow-build=@google/genai \
  --allow-build=koffi \
  --allow-build=node-pty \
  --allow-build=protobufjs \
  @deepseek-ai/dsh web

• Is it possible that @deepseek-ai/dsh can be designed as a global package? For example?

pnpm add --global \
  --allow-build=@deepseek-ai/dsh-subprocess-local \
  --allow-build=@google/genai \
  --allow-build=koffi \
  --allow-build=node-pty \
  --allow-build=protobufjs \
  opencode-ai

dsh web

• In comparison, dsh web is much simpler. If this is already possible, shouldn't the documentation be updated accordingly? Currently, git doesn't even have a PR area open, so it's hard to say I know what to do.