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/app/workspace/layout.tsx

@@ -1,12 +1,12 @@
 "use client";
 
 import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
-import { useCallback, useEffect, useState } from "react";
+import { useCallback, useEffect, useLayoutEffect, useState } from "react";
 import { Toaster } from "sonner";
 
 import { SidebarInset, SidebarProvider } from "@/components/ui/sidebar";
 import { WorkspaceSidebar } from "@/components/workspace/workspace-sidebar";
-import { useLocalSettings } from "@/core/settings";
+import { getLocalSettings, useLocalSettings } from "@/core/settings";
 
 const queryClient = new QueryClient();
 
@@ -14,7 +14,11 @@ export default function WorkspaceLayout({
   children,
 }: Readonly<{ children: React.ReactNode }>) {
   const [settings, setSettings] = useLocalSettings();
-  const [open, setOpen] = useState(() => !settings.layout.sidebar_collapsed);
+  const [open, setOpen] = useState(false); // SSR default: open (matches server render)
+  useLayoutEffect(() => {
+    // Runs synchronously before first paint on the client — no visual flash
+    setOpen(!getLocalSettings().layout.sidebar_collapsed);
+  }, []);
   useEffect(() => {
     setOpen(!settings.layout.sidebar_collapsed);
   }, [settings.layout.sidebar_collapsed]);