Improve starter reference documentation

I'm pretty sure several years ago looking at whatever tech on spring boot's docs it would advise to pull certain starters. These days I don't see any mention of those starters anywhere except this simple table with 1 line descriptions.

For example, looking at how to set up JSR 303 Bean Validation, core docs only say I need "JSR-303 implementation (such as Hibernate validator)" on the classpath, then I gotta go their docs and it also says some sort of "Jakarta Expression Language" is also required but doesn't mention if Spring Boot requires it or not. After some digging, I found there's "spring-boot-starter-validation" that actually pulls Tomcat-specific EL dependency along with the Hibernate Validator.

Why don't the docs mention any of that? And that doesn't only apply to validation, I don't ever see any starters or dependencies or proper setup instructions for things. Another example with AOP Load-Time Weaving, I spent several days setting this up, some info was in javadocs, some was vaguely explained in the docs, and finally baeldung had the full setup documented after which it finally worked - although it was not about starters that time but still required dependencies aren't documented.

I see Spring push for their initializer which has all the starters but I only create a project once, after that I don't ever look at that. I could've sworn like 5 years ago the docs were explaining all that, what happened?

At this point, I might prefer going to baeldung instead of actual spring docs.

Start with the starter table in reference/using/build-systems.html and the validation page, then inspect the linked spring-boot-starter-validation/build.gradle entry for the dependencies it brings in. Define a focused documentation scope and update the relevant starter, dependency, and setup guidance so users can identify required components without relying on external guides.