Restructure OAuth2 client auto-configuration

Previously, OAuth2 client auto-configuration was managed by a single
class:

- OAuth2ClientAutoConfiguration for servlet apps
- ReactiveOAuth2ClientAutoConfiguration for reactive apps

OAuth2ClientAutoConfiguration being for servlet apps meant that
a blocking OAuth2 client was not availabile in a non-web application.

The auto-configuration classes did two things:

- Auto-configured beans that are specific to server-side web security
  that uses an OAuth2 client
- Auto-configured OAuth2 client beans that may be used client- or
  server-side

Combining these two things into a single auto-configuration class
meant that you could not choose to use one or the other. For example,
you may want to make use of an OAuth2 client in a web application
without also using OAuth2 client-based web security.

This commit restructures the auto-configuration to address these
problems. There are now two auto-configurations for non-reactive apps:

- OAuth2ClientAutoConfiguration
- OAuth2ClientWebSecurityAutoConfiguration

and two auto-configurations for reactive apps:

- ReactiveOAuth2ClientAutoConfiguration
- ReactiveOAuth2ClientWebSecurityAutoConfiguration

This separation allows one to be used without the other. Furthermore,
the conditions have been updated so that, for example, the blocking
OAuth2 client is available in a non-web application.

Closes gh-40997
Closes gh-44906

Co-authored-by: Moritz Halbritter <moritz.halbritter@broadcom.com>

spring-boot-project/spring-boot-test-autoconfigure/src/main/resources/META-INF/spring/org.springframework.boot.test.autoconfigure.web.reactive.AutoConfigureWebTestClient.imports

@@ -1,5 +1,6 @@
 # AutoConfigureWebClient auto-configuration imports
 org.springframework.boot.autoconfigure.security.oauth2.client.reactive.ReactiveOAuth2ClientAutoConfiguration
+org.springframework.boot.autoconfigure.security.oauth2.client.reactive.ReactiveOAuth2ClientWebSecurityAutoConfiguration
 org.springframework.boot.autoconfigure.security.oauth2.resource.reactive.ReactiveOAuth2ResourceServerAutoConfiguration
 org.springframework.boot.autoconfigure.security.reactive.ReactiveSecurityAutoConfiguration
 org.springframework.boot.autoconfigure.security.reactive.ReactiveUserDetailsServiceAutoConfiguration

spring-boot-project/spring-boot-test-autoconfigure/src/main/resources/META-INF/spring/org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc.imports

@@ -2,8 +2,9 @@
 org.springframework.boot.test.autoconfigure.web.servlet.MockMvcAutoConfiguration
 org.springframework.boot.test.autoconfigure.web.servlet.MockMvcWebClientAutoConfiguration
 org.springframework.boot.test.autoconfigure.web.servlet.MockMvcWebDriverAutoConfiguration
-org.springframework.boot.autoconfigure.security.oauth2.client.servlet.OAuth2ClientAutoConfiguration
+org.springframework.boot.autoconfigure.security.oauth2.client.OAuth2ClientAutoConfiguration
 org.springframework.boot.autoconfigure.security.oauth2.resource.servlet.OAuth2ResourceServerAutoConfiguration
+org.springframework.boot.autoconfigure.security.oauth2.client.servlet.OAuth2ClientWebSecurityAutoConfiguration
 org.springframework.boot.autoconfigure.security.servlet.SecurityAutoConfiguration
 org.springframework.boot.autoconfigure.security.servlet.SecurityFilterAutoConfiguration
 org.springframework.boot.autoconfigure.security.servlet.UserDetailsServiceAutoConfiguration

spring-boot-project/spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/web/servlet/WebMvcTestAutoConfigurationIntegrationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -22,7 +22,7 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.autoconfigure.freemarker.FreeMarkerAutoConfiguration;
 import org.springframework.boot.autoconfigure.groovy.template.GroovyTemplateAutoConfiguration;
 import org.springframework.boot.autoconfigure.mustache.MustacheAutoConfiguration;
-import org.springframework.boot.autoconfigure.security.oauth2.client.servlet.OAuth2ClientAutoConfiguration;
+import org.springframework.boot.autoconfigure.security.oauth2.client.OAuth2ClientAutoConfiguration;
 import org.springframework.boot.autoconfigure.security.oauth2.resource.servlet.OAuth2ResourceServerAutoConfiguration;
 import org.springframework.boot.autoconfigure.task.TaskExecutionAutoConfiguration;
 import org.springframework.boot.autoconfigure.thymeleaf.ThymeleafAutoConfiguration;