Document a "starter workflow" for devs to test that they have a fully-working dev env.

[seanlip]

Provide a "developer readiness/starter kit" wiki page that gives developers a checklist to verify that they have a fully-working dev env for Oppia Web. Things to check:

• Start the local dev server in reasonable time.
• Make changes to the code, and have those changes show up on the local server almost immediately, without them having to restart it.
• View backend + frontend logs and stack traces when running the dev server.
• Run individual tests on the local machine in reasonable time. Verify this for: backend tests, frontend tests, e2e tests, acceptance tests, typescript checks, mypy checks. (Consider asking them to report if the time needed to run a single test in each of these categories is greater than some threshold.)
• View errors / stack traces when tests fail. To check this, introduce an error in the code, and make sure they can see the resulting console.log() (or equivalent) statements. Do this for each of the backend, frontend, e2e and acceptance tests.