refactor(framework): add @Shutdown annotation to AgentContext for ordered shutdown hook execution

Partner-Framework/src/main/java/work/slhaf/partner/api/agent/factory/context/AgentContext.kt

@@ -108,3 +108,15 @@ sealed class ModuleContextData<out T : AbstractAgentModule> {
         val basePrompt: JSONArray
     )
 }
+
+/**
+ * # Shutdown Hook 注解
+ * - 可用于[AgentComponent]相关类、[work.slhaf.partner.api.agent.factory.capability.annotation.CapabilityCore]相关类。
+ * - 关闭时将按照：Running -> Additional -> Standalone -> Sub -> Capability 的顺序执行
+ * - [order] 仅在同一层级内起顺序对比作用，数值越小，执行越早。
+ */
+@Retention(AnnotationRetention.RUNTIME)
+@Target(AnnotationTarget.FUNCTION)
+annotation class Shutdown(
+    val order: Int = 0,
+)