Change npm packaging structure and fix contributing info (#16)

* change the package to workspace concept

* add provider name and change default model

* add the node_modules to git ignore

* change the npm runs to use workspace

* fix the start scripts to use the workspace

* update the uv.lock

* updated instructions

* update the docker build to use the npm workspace

* Update package-lock.json after merge to sync workspace dependencies

* fix merge conflict