Setup npm workspaces for shared code

[dotNomad]

To share non-CommonJS code, like TypeScript code, we need bundling first so this is on hold until https://github.com/posit-dev/publisher/issues/1289 is complete.

---

NPM workspaces will allow us to import packages in the repo into other packages for very easy code re-use and isolation. This work spurred out of the sharing of the api module and it having issues between VSCode and the standalone-UI. Keeping those the same is a challenge that a monorepo setup with npm workspaces solves in addition to allowing to create as many shared modules as we need.

[dotNomad]

Some helpful references:

• https://github.com/microsoft/vscode-vsce/issues/381
• https://github.com/microsoft/vscode-vsce/issues/580
• https://github.com/mdx-js/mdx-analyzer/pull/371
• https://github.com/mdx-js/mdx-analyzer/blob/main/packages/vscode-mdx/.vscodeignore
• https://github.com/vercel/turbo/tree/main/examples/with-npm

[dotNomad]

sourcegraph is a good example of a monorepo with frontend and Go organization