Turn the example apps into templates and add a project scaffolder

[zantvoort]

The three storm-example-* repositories are clone-and-run, but nothing guides a new user to them as the starting point for their own project.

Two pieces. Mark the example repositories as GitHub template repositories, which adds the "Use this template" button at no cost. And teach the npm CLI to scaffold: npx @storm-orm/cli new, prompting for language and framework (Spring Boot with Java or Kotlin, Ktor with Kotlin) plus database, producing a runnable project preconfigured with H2.

Tasks:

• Mark storm-example-* as template repositories
• storm new in the CLI covering the three language/framework combinations
• Release workflow keeps template versions current
• Link the templates from the README and docs