feat(dashboard): extract inline script to standalone dashboard.ts/js, add UI build/check recipes, and add route unit tests

server/src/models.rs

@@ -309,6 +309,17 @@ pub struct AgentSignal {
     pub ttl_seconds: Option<u64>,
 }
 
+#[derive(Debug, Clone, Serialize, Deserialize, Default)]
+pub struct TaskEvent {
+    pub task_id: String,
+    pub status: String,
+    pub action: Option<String>,
+    pub result: Option<serde_json::Value>,
+    pub error: Option<String>,
+    pub timestamp: u64,
+    pub session_id: Option<String>,
+}
+
 #[cfg(test)]
 mod tests {
     use axum::http::StatusCode;