✨ feat: Implement Resumable Generation Jobs with SSE Support

- Introduced GenerationJobManager to handle resumable LLM generation jobs independently of HTTP connections.
- Added support for subscribing to ongoing generation jobs via SSE, allowing clients to reconnect and receive updates without losing progress.
- Enhanced existing agent controllers and routes to integrate resumable functionality, including job creation, completion, and error handling.
- Updated client-side hooks to manage adaptive SSE streams, switching between standard and resumable modes based on user settings.
- Added UI components and settings for enabling/disabling resumable streams, improving user experience during unstable connections.

api/server/services/Endpoints/agents/initialize.js

@@ -65,18 +65,21 @@ const initializeClient = async ({ req, res, signal, endpointOption }) => {
   }
   const appConfig = req.config;
 
-  // TODO: use endpointOption to determine options/modelOptions
+  /** @type {string | null} */
+  const streamId = req._resumableStreamId || null;
+
   /** @type {Array<UsageMetadata>} */
   const collectedUsage = [];
   /** @type {ArtifactPromises} */
   const artifactPromises = [];
   const { contentParts, aggregateContent } = createContentAggregator();
-  const toolEndCallback = createToolEndCallback({ req, res, artifactPromises });
+  const toolEndCallback = createToolEndCallback({ req, res, artifactPromises, streamId });
   const eventHandlers = getDefaultHandlers({
     res,
     aggregateContent,
     toolEndCallback,
     collectedUsage,
+    streamId,
   });
 
   if (!endpointOption.agent) {