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/components/workspace/messages/context.ts

@@ -1,11 +1,11 @@
-import type { UseStream } from "@langchain/langgraph-sdk/react";
+import type { BaseStream } from "@langchain/langgraph-sdk/react";
 import { createContext, useContext } from "react";
 
 import type { AgentThreadState } from "@/core/threads";
 
 export interface ThreadContextType {
-  threadId: string;
-  thread: UseStream<AgentThreadState>;
+  thread: BaseStream<AgentThreadState>;
+  isMock?: boolean;
 }
 
 export const ThreadContext = createContext<ThreadContextType | undefined>(

frontend/src/components/workspace/messages/message-list-item.tsx

@@ -46,22 +46,24 @@ export function MessageListItem({
         message={message}
         isLoading={isLoading}
       />
-      <MessageToolbar
-        className={cn(
-          isHuman ? "-bottom-9 justify-end" : "-bottom-8",
-          "absolute right-0 left-0 z-20 opacity-0 transition-opacity delay-200 duration-300 group-hover/conversation-message:opacity-100",
-        )}
-      >
-        <div className="flex gap-1">
-          <CopyButton
-            clipboardData={
-              extractContentFromMessage(message) ??
-              extractReasoningContentFromMessage(message) ??
-              ""
-            }
-          />
-        </div>
-      </MessageToolbar>
+      {!isLoading && (
+        <MessageToolbar
+          className={cn(
+            isHuman ? "-bottom-9 justify-end" : "-bottom-8",
+            "absolute right-0 left-0 z-20 opacity-0 transition-opacity delay-200 duration-300 group-hover/conversation-message:opacity-100",
+          )}
+        >
+          <div className="flex gap-1">
+            <CopyButton
+              clipboardData={
+                extractContentFromMessage(message) ??
+                extractReasoningContentFromMessage(message) ??
+                ""
+              }
+            />
+          </div>
+        </MessageToolbar>
+      )}
     </AIElementMessage>
   );
 }

frontend/src/components/workspace/messages/message-list.tsx

@@ -1,5 +1,4 @@
-import type { Message } from "@langchain/langgraph-sdk";
-import type { UseStream } from "@langchain/langgraph-sdk/react";
+import type { BaseStream } from "@langchain/langgraph-sdk/react";
 
 import {
   Conversation,
@@ -34,19 +33,18 @@ export function MessageList({
   className,
   threadId,
   thread,
-  messages,
   paddingBottom = 160,
 }: {
   className?: string;
   threadId: string;
-  thread: UseStream<AgentThreadState>;
-  messages: Message[];
+  thread: BaseStream<AgentThreadState>;
   paddingBottom?: number;
 }) {
   const { t } = useI18n();
   const rehypePlugins = useRehypeSplitWordsIntoSpans(thread.isLoading);
   const updateSubtask = useUpdateSubtask();
-  if (thread.isThreadLoading) {
+  const messages = thread.messages;
+  if (thread.isThreadLoading && messages.length === 0) {
     return <MessageListSkeleton />;
   }
   return (