Exercise 3: A .gitignore and a Re-Runnable Script — Possible Solution
=======================================================================

.gitignore:

  node_modules/        # installed packages; recreated with npm install
  .env                 # database URLs and passwords — never commit secrets
  generated/           # the generated Prisma Client; recreated with
                       # npx prisma generate, and specific to this machine
  *.db                 # the SQLite database file (your local data)
  *.db-journal         # SQLite's temporary journal file

Do commit prisma/schema.prisma, prisma/migrations/, the config file,
package.json and package-lock.json: they describe the project, and
another developer needs them to recreate it.

A tip: commit a .env.example with a placeholder value, so others know
which variables to set.

Making script.ts safe to run twice — use upsert (covered properly in
Chapter 5), which updates the row if it exists and creates it if not:

  const user = await prisma.user.upsert({
    where:  { email: "ada@example.com" },
    update: {},
    create: { email: "ada@example.com", name: "Ada" },
  });

Running the script again now finds the existing Ada instead of
failing on the unique email.

WHY THIS WORKS AS AN ANSWER
------------------------------
It separates files you can regenerate or must keep private from files
that define the project, and fixes the duplicate-email failure the
chapter pointed out without deleting any data.