fix(scripts): use ts-node for start script

[caugner]

Before

% npm start

> [email protected] start
> node app.js

node:internal/modules/cjs/loader:1228
  throw err;
  ^

Error: Cannot find module '/Users/claas/github/openwebdocs/mdn-bcd-collector/app.js'
    at Module._resolveFilename (node:internal/modules/cjs/loader:1225:15)
    at Module._load (node:internal/modules/cjs/loader:1051:27)
    at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:174:12)
    at node:internal/main/run_main_module:28:49 {
  code: 'MODULE_NOT_FOUND',
  requireStack: []
}

Node.js v20.18.0

After

% npm start

> [email protected] start
> node --loader=ts-node/esm --no-warnings=ExperimentalWarning app.ts

info: Listening on port 8080 (HTTP)
info: Press Ctrl+C to quit.

[queengooborg]

ts-node is a dev dependency and is not available in production environments. The expectation for production is to build everything first on a development environment, then run the built version in production, which is what Heroku does. (I also had problems with trying to use ts-node in Heroku's production environment.)

TLDR, the start script should not use ts-node. Developers should always use npm run dev, but if they absolutely must run npm start, run npm build first.