finish `create-worktop` setup tool

[lukeed]

Imported from #129

• [ ] --cfw (or --monorepo ??) for monorepo/multi-worker setup Should use cfw to build/deploy Workers
  • replaces wrangler for deployment (if --env is cloudflare)
  • replaces worktop.build for build system
• [x] --env and --format combinations
  • --env – sets the platform/environment target
    • default: "cfw" | "cloudflare"
    • options: "cfw" | "cloudflare" | "browser" | "deno" | "node"
  • --format – depends on --env value
    • "cfw" :: "module" (default) | "sw"
    • "browser" :: "sw" (default)
    • "deno" :: N/A
    • "node" :: None (default) | "function" for GCP Functions | "lambda" for AWS lambda family

[lukeed]

Planned usage should look like this:

# setup Worker w/ Cloudflare Module Worker (default)
$ npm init worktop <dir>
$ npm init worktop <dir> --env cloudflare
$ npm init worktop <dir> --env cloudflare --format module

# setup Worker w/ Cloudflare Service Worker ("deprecated")
$ npm init worktop <dir> --format sw
$ npm init worktop <dir> --env cloudflare --format sw

# setup web Service Worker (web)
$ npm init worktop <dir> --env web
$ npm init worktop <dir> --env web --format sw

# setup for Deno project
$ npm init worktop <dir> --env deno

# setup for Node.js project
$ npm init worktop <dir> --env node

# setup for Node.js project :: GCP Functions
$ npm init worktop <dir> --env node --format function

# setup for Node.js project :: AWS Lambda-like
$ npm init worktop <dir> --env node --format lambda