Motivation

• Bring the project baseline to a modern Java and Spring Boot platform to allow using Spring Boot 3.x and Jakarta namespaces.
• Prepare dependency BOMs and libraries for Spring Boot 3 compatibility and remove Boot 2-era auto-config packages.
• Update compilation target to a current LTS/modern JDK to align with the chosen Spring Boot release.

Description

• Updated pom.xml to set maven.compiler.source/maven.compiler.target to 21 and java.version to 21, and upgraded springboot.version to 3.5.0.
• Bumped platform BOMs: spring-cloud-dependencies -> 2024.0.0 and spring-cloud-gcp-dependencies -> 6.1.0.
• Removed the deprecated org.springframework.security.oauth.boot:spring-security-oauth2-autoconfigure dependency and migrated resilience4j-spring-boot2 -> resilience4j-spring-boot3.
• Replaced springdoc-openapi-ui with springdoc-openapi-starter-webmvc-ui (2.8.8) for Spring Boot 3 compatibility.
• Replaced javax.* imports with jakarta.* in API, config, integration and security classes (17 files updated, including controllers, SimpleCORSFilter, MyLogoutSuccessHandler, and IntegrationProviderFactory).
• Committed the changes as a single upgrade baseline (commit message: Upgrade to Java 21 and Spring Boot 3 baseline).

Testing

• Ran mvn -Dexec.skip=true -DskipTests compile, which failed due to inability to resolve BOMs and dependencies because Maven Central requests returned HTTP 403 in this environment, so dependency resolution could not complete.
• Ran mvn -Dexec.skip=true -DskipTests validate, which likewise failed for the same network/403 reason and reported missing managed dependency versions.
• Ran repository-wide search/replace and automated source updates for javax -> jakarta substitutions (scripted replacement completed successfully in the workspace).

Codex Task