feat(agent):Supports custom agent and chat experience with refactoring (#957)

* feat: add agent management functionality with creation, editing, and deletion

* feat: enhance agent creation and chat experience

- Added AgentWelcome component to display agent description on new thread creation.
- Improved agent name validation with availability check during agent creation.
- Updated NewAgentPage to handle agent creation flow more effectively, including enhanced error handling and user feedback.
- Refactored chat components to streamline message handling and improve user experience.
- Introduced new bootstrap skill for personalized onboarding conversations, including detailed conversation phases and a structured SOUL.md template.
- Updated localization files to reflect new features and error messages.
- General code cleanup and optimizations across various components and hooks.

* Refactor workspace layout and agent management components

- Updated WorkspaceLayout to use useLayoutEffect for sidebar state initialization.
- Removed unused AgentFormDialog and related edit functionality from AgentCard.
- Introduced ArtifactTrigger component to manage artifact visibility.
- Enhanced ChatBox to handle artifact selection and display.
- Improved message list rendering logic to avoid loading states.
- Updated localization files to remove deprecated keys and add new translations.
- Refined hooks for local settings and thread management to improve performance and clarity.
- Added temporal awareness guidelines to deep research skill documentation.

* feat: refactor chat components and introduce thread management hooks

* feat: improve artifact file detail preview logic and clean up console logs

* feat: refactor lead agent creation logic and improve logging details

* feat: validate agent name format and enhance error handling in agent setup

* feat: simplify thread search query by removing unnecessary metadata

* feat: update query key in useDeleteThread and useRenameThread for consistency

* feat: add isMock parameter to thread and artifact handling for improved testing

* fix: reorder import of setup_agent for consistency in builtins module

* feat: append mock parameter to thread links in CaseStudySection for testing purposes

* fix: update load_agent_soul calls to use cfg.name for improved clarity

* fix: update date format in apply_prompt_template for consistency

* feat: integrate isMock parameter into artifact content loading for enhanced testing

* docs: add license section to SKILL.md for clarity and attribution

* feat(agent): enhance model resolution and agent configuration handling

* chore: remove unused import of _resolve_model_name from agents

* feat(agent): remove unused field

* fix(agent): set default value for requested_model_name in _resolve_model_name function

* feat(agent): update get_available_tools call to handle optional agent_config and improve middleware function signature

---------

Co-authored-by: Willem Jiang <willem.jiang@gmail.com>

frontend/src/core/threads/hooks.ts

@@ -1,42 +1,63 @@
-import type { HumanMessage } from "@langchain/core/messages";
 import type { AIMessage } from "@langchain/langgraph-sdk";
 import type { ThreadsClient } from "@langchain/langgraph-sdk/client";
 import { useStream, type UseStream } from "@langchain/langgraph-sdk/react";
 import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
-import { useCallback } from "react";
+import { useCallback, useState } from "react";
 import { toast } from "sonner";
 
 import type { PromptInputMessage } from "@/components/ai-elements/prompt-input";
 
 import { getAPIClient } from "../api";
+import type { LocalSettings } from "../settings";
 import { useUpdateSubtask } from "../tasks/context";
 import { uploadFiles } from "../uploads";
 
-import type {
-  AgentThread,
-  AgentThreadContext,
-  AgentThreadState,
-} from "./types";
+import type { AgentThread, AgentThreadState } from "./types";
+
+export type ToolEndEvent = {
+  name: string;
+  data: unknown;
+};
+
+export type ThreadStreamOptions = {
+  threadId?: string | null | undefined;
+  context: LocalSettings["context"];
+  isMock?: boolean;
+  onStart?: (threadId: string) => void;
+  onFinish?: (state: AgentThreadState) => void;
+  onToolEnd?: (event: ToolEndEvent) => void;
+};
 
 export function useThreadStream({
   threadId,
-  isNewThread,
+  context,
+  isMock,
+  onStart,
   onFinish,
-}: {
-  isNewThread: boolean;
-  threadId: string | null | undefined;
-  onFinish?: (state: AgentThreadState) => void;
-}) {
+  onToolEnd,
+}: ThreadStreamOptions) {
+  const [_threadId, setThreadId] = useState<string | null>(threadId ?? null);
   const queryClient = useQueryClient();
   const updateSubtask = useUpdateSubtask();
   const thread = useStream<AgentThreadState>({
-    client: getAPIClient(),
+    client: getAPIClient(isMock),
     assistantId: "lead_agent",
-    threadId: isNewThread ? undefined : threadId,
+    threadId: _threadId,
     reconnectOnMount: true,
     fetchStateHistory: { limit: 1 },
+    onCreated(meta) {
+      setThreadId(meta.thread_id);
+      onStart?.(meta.thread_id);
+    },
+    onLangChainEvent(event) {
+      if (event.event === "on_tool_end") {
+        onToolEnd?.({
+          name: event.name,
+          data: event.data,
+        });
+      }
+    },
     onCustomEvent(event: unknown) {
-      console.info(event);
       if (
         typeof event === "object" &&
         event !== null &&
@@ -76,25 +97,13 @@ export function useThreadStream({
       );
     },
   });
-  return thread;
-}
 
-export function useSubmitThread({
-  threadId,
-  thread,
-  threadContext,
-  isNewThread,
-  afterSubmit,
-}: {
-  isNewThread: boolean;
-  threadId: string | null | undefined;
-  thread: UseStream<AgentThreadState>;
-  threadContext: Omit<AgentThreadContext, "thread_id">;
-  afterSubmit?: () => void;
-}) {
-  const queryClient = useQueryClient();
-  const callback = useCallback(
-    async (message: PromptInputMessage) => {
+  const sendMessage = useCallback(
+    async (
+      threadId: string,
+      message: PromptInputMessage,
+      extraContext?: Record<string, unknown>,
+    ) => {
       const text = message.text.trim();
 
       // Upload files first if any
@@ -163,10 +172,10 @@ export function useSubmitThread({
                 },
               ],
             },
-          ] as HumanMessage[],
+          ],
         },
         {
-          threadId: isNewThread ? threadId! : undefined,
+          threadId: threadId,
           streamSubgraphs: true,
           streamResumable: true,
           streamMode: ["values", "messages-tuple", "custom"],
@@ -174,17 +183,21 @@ export function useSubmitThread({
             recursion_limit: 1000,
           },
           context: {
-            ...threadContext,
+            ...extraContext,
+            ...context,
+            thinking_enabled: context.mode !== "flash",
+            is_plan_mode: context.mode === "pro" || context.mode === "ultra",
+            subagent_enabled: context.mode === "ultra",
             thread_id: threadId,
           },
         },
       );
       void queryClient.invalidateQueries({ queryKey: ["threads", "search"] });
-      afterSubmit?.();
+      // afterSubmit?.();
     },
-    [thread, isNewThread, threadId, threadContext, queryClient, afterSubmit],
+    [thread, context, queryClient],
   );
-  return callback;
+  return [thread, sendMessage] as const;
 }
 
 export function useThreads(