Close DDD cleanup and tests-support closure

server-rs/crates/module-runtime-story/src/errors.rs

@@ -1,3 +1,26 @@
-//! runtime story 领域错误过渡落位。
+//! runtime story 领域错误。
 //!
 //! 错误只表达运行时剧情规则失败，不能直接绑定 HTTP 或数据库错误模型。
+
+use std::{error::Error, fmt};
+
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub enum RuntimeStoryRuleError {
+    MissingRuntimeSessionId,
+    MissingStoryAction,
+    UnsupportedStoryAction,
+    InvalidRuntimeSnapshot,
+}
+
+impl fmt::Display for RuntimeStoryRuleError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            Self::MissingRuntimeSessionId => f.write_str("runtime_story.session_id 不能为空"),
+            Self::MissingStoryAction => f.write_str("runtime_story.action 不能为空"),
+            Self::UnsupportedStoryAction => f.write_str("runtime_story.action 当前不受支持"),
+            Self::InvalidRuntimeSnapshot => f.write_str("runtime_story.snapshot 非法"),
+        }
+    }
+}
+
+impl Error for RuntimeStoryRuleError {}