fix: cap agent abort and disconnect partial saves to the parent expiry

The agents /chat/abort endpoint and the resumable disconnect handler save a
partial response through saveMessage without saveConvo following, but did not
pass capExpiryToConversation. In an ephemeral deployment with a parent that
already has an earlier active expiredAt, the partial response got a freshly
computed later deadline and outlived its conversation.

Pass the same cap metadata used by the other message-only abort path so the
partial response cannot outlive its parent. If generation later completes, the
normal response-end save re-stamps the message with a fresh deadline.

api/server/controllers/agents/request.js

@@ -315,7 +315,10 @@ const ResumableAgentController = async (req, res, next, initializeClient, addTit
             interfaceConfig: req?.config?.interfaceConfig,
           },
           partialMessage,
-          { context: 'api/server/controllers/agents/request.js - partial response on disconnect' },
+          {
+            context: 'api/server/controllers/agents/request.js - partial response on disconnect',
+            capExpiryToConversation: true,
+          },
         );
 
         logger.debug(

api/server/routes/agents/__tests__/abort.spec.js

@@ -285,6 +285,7 @@ describe('Agent Abort Endpoint', () => {
           }),
           expect.objectContaining({
             context: 'api/server/routes/agents/index.js - abort endpoint',
+            capExpiryToConversation: true,
           }),
         );
       });

api/server/routes/agents/index.js

@@ -313,7 +313,10 @@ router.post('/chat/abort', configMiddleware, async (req, res) => {
             interfaceConfig: req?.config?.interfaceConfig,
           },
           responseMessage,
-          { context: 'api/server/routes/agents/index.js - abort endpoint' },
+          {
+            context: 'api/server/routes/agents/index.js - abort endpoint',
+            capExpiryToConversation: true,
+          },
         );
         logger.debug(`[AgentStream] Saved partial response for: ${jobStreamId}`);
       } catch (saveError) {