gj.spring.pf4j — Pluggable Authentication for Plugin Controllers. Two-layer provider API: AbstractPluginAuthenticationProvider (simple, single-strategy) and IPluginAuthenticationProvider (advanced, multi-provider routing with supports()). Strategy-driven provider chain: AtLeastOneSuccessfulStrategy (default) and FirstSuccessfulStrategy, both pluggable via AuthenticationStrategy bean override. Dual-stack auth filters: PluginDelegatingAuthFilter (MVC Servlet) and ...