- Added a `ThemeProvider` component to manage theme state and persist it in local storage.
- Introduced a `ModeToggle` component for switching between light, dark, and system themes.
- Updated the `Layout` component to include the `ThemeProvider`.
- Enhanced the `AppSidebar` to include the `ModeToggle` for user accessibility.
- Added a new `DropdownMenu` component with various subcomponents including `DropdownMenuTrigger`, `DropdownMenuContent`, and more.
- Updated `package.json` to include `@radix-ui/react-dropdown-menu` as a dependency.
- Updated `pnpm-lock.yaml` to reflect the new dependency and its version.
