Docs: Missing prisma migrate dev step in "Creating the Application" section of Full Stack tutorial

[sanchitrk]

While following the "Full Stack Applications > Creating the Application" tutorial, I encountered a Prisma database error during the user authentication step.

It turned out that I needed to run bun run migrate:dev to apply the migrations locally. This step isn't currently mentioned in the tutorial, and adding it would help others avoid confusion or runtime errors.

[ahaywood]

🤔 This command should get run automatically, as soon as you run pnpm run dev