Closes gh-12952

* gh-12784:
  Polish “Only analyze configurations that we've registered to check”
  Only analyze configurations that we've registered to check

Closes gh-12784

See gh-12784

See gh-12784

Since https://jira.spring.io/browse/SPR-16624, the contract for
`ContentNegotiationStrategy` has been refined and should never return an
empty list if it's got no preference for a media type, but it should
rather respond with a `"*/*"` instead.

This commit fixes the `OptionalPathExtensionContentNegotiationStrategy`
defined in the Spring MVC auto-configuration to have that behavior.

Fixes gh-12900

Closes gh-12912

As we've updated the complete ref doc to use a canonical format for
configuration keys, this not is outdated and this commit removes it.

Closes gh-12940

* pr/12922:
  Replace <code> tags where possible

Closes gh-12922

Fixes gh-11395

* pr/12877:
  Add reference to javamelody starter

Closes gh-12877

See gh-11380

This commit includes some refactoring of active profiles
processing. Previously, there was a LIFO Queue for adding active
profiles. Profiles that were added last, were processed first.
Because of this reverse ordering, profiles were prepended to the
environment to preserve the order in which they were logged.
This however didn't work for "included" profiles as they were
prepended to the environment even though they were processed after
the active profile. In this commit, profiles are processed in a FIFO manner
and processed as they're found.

Fixes gh-11380

* pr/12895:
  Fix additional missing semicolon on sample code
  Add missing semicolon on sample code

Closes gh-12895

See gh-12895

* pr/12894:
  Polish "Less object instantiation in WebMvcTags"
  Less object instantiation in WebMvcTags