story-kit: merge 149_bug_web_ui_does_not_update_when_agents_are_started_or_stopped

server/src/io/watcher.rs

@@ -45,6 +45,10 @@ pub enum WatcherEvent {
     },
     /// `.story_kit/project.toml` was modified at the project root (not inside a worktree).
     ConfigChanged,
+    /// An agent's state changed (started, stopped, completed, etc.).
+    /// Triggers a pipeline state refresh so the frontend can update agent
+    /// assignments without waiting for a filesystem event.
+    AgentStateChanged,
 }
 
 /// Return `true` if `path` is the root-level `.story_kit/project.toml`, i.e.