Closes gh-21574

Closes gh-21587

* pr/21579:
  Polish "Polish duration support javadoc"
  Polish duration support javadoc

Closes gh-21579

See gh-21579

See gh-21579

This commit restores RestClientBuilderCustomizer in the rest package in
a deprecated fashion so that the upgrade from 2.2 is smoother.

Closes gh-21572

Previously, the productionRuntimeClasspath configuration was created
without any attributes. This caused problems with multi-project
dependency resolution as there was insufficient information for Gradle
to determine which variant of a dependency should be used by the
productionRuntimeClasspath configuration.

This commit updates the configuration to have three attributes, each
configured with the same values as those of Gradle's own
runtimeClasspathConfiguration.

Fixes gh-21549

Closes gh-21440

Closes gh-21563

* pr/21540:
  Fix links for Apache Camel starter

Closes gh-21540

See gh-21540

* pr/21492:
  Fix default value for spring.data.jpa.repositories.bootstrap-mode

Closes gh-21492

See gh-21492

Closes gh-21562

* pr/21480:
  Polish "Use the container IP address for tests using TestContainer"
  Use the container IP address for tests using TestContainer

Closes gh-21480

See gh-21480

See gh-21480

Closes gh-21560

See gh-21392

* pr/21392:
  Fix uri tag for empty path

Closes gh-21392

See gh-21392

This commit mentions the `management.health.probes.enabled`
configuration property in the Kubernetes Probes section of the Actuator
chapter.

Enabling this property is required if we need to expose Kubernetes
Probes in a non-Kubernetes environment.

Fixes gh-21505

Prior to this commit, Spring Boot would auto-configure Spring MVC and
would keep the default `UrlPathHelper` configuration.
Since Spring Boot is in charge of configuring the `DispatcherServlet`
and its mapping, it is in a position to optimally configure the
`UrlPathHelper` depending on the chosen mapping.

This commit sets the `alwaysUseFullPath` property of `UrlPathHelper` if
the Servlet mapping is `"/"`. This is more efficient since this
configuration requires less processing of the request path.

Closes gh-21499

This commit adds the support for static and templated welcome pages with
Spring WebFlux. The implementation is backed by a `RouterFunction`
that's serving a static `index.html` file or rendering an `index` view.

Closes gh-9785

Prior to this commit, a default tag of 'latest' was used when no tag
was included in the builder image name used when building an image in
the Maven and Gradle plugins, but the tag for the run image was left
empty if it was not provided. This resulted in errors when pulling
the run image from an image repository. This commit applies the
same tag defaulting logic to the run image name.

Fixes gh-21532

Closes gh-21529

* pr/21485:
  Fix typo in section 4.30.6

Closes gh-21485

See gh-21485

* pr/21509:
  Avoid allocations in ConfigFileApplicationListener

Closes gh-21509

See gh-21509

Closes gh-21524

Closes gh-21526

Closes gh-21525

Closes gh-21528

Closes gh-21527

Closes gh-21282

* gh-21490:
  Polish `Add gradle build image command line example`
  Add gradle build image command line example

Closes gh-21490

See gh-21490

See gh-21490