fix(agents): cancel active runs before delete

server/src/routes/agents.ts

@@ -2029,6 +2029,7 @@ export function agentRoutes(db: Db) {
   router.delete("/agents/:id", async (req, res) => {
     assertBoard(req);
     const id = req.params.id as string;
+    await heartbeat.cancelActiveForAgent(id, "Cancelled because the agent was deleted");
     const agent = await svc.remove(id);
     if (!agent) {
       res.status(404).json({ error: "Agent not found" });

server/src/services/heartbeat.ts

@@ -4585,7 +4585,7 @@ export function heartbeatService(db: Db) {
 
     cancelRun: (runId: string) => cancelRunInternal(runId),
 
-    cancelActiveForAgent: (agentId: string) => cancelActiveForAgentInternal(agentId),
+    cancelActiveForAgent: (agentId: string, reason?: string) => cancelActiveForAgentInternal(agentId, reason),
 
     cancelBudgetScopeWork,