feat(docs): migrate documentation site into monorepo (#5912)

apps/docs/src/declarations.d.ts

@@ -0,0 +1,25 @@
+declare module "*.mp4" {
+  const src: string;
+  export default src;
+}
+
+declare module "@theme/Tabs" {
+  import type { ComponentProps, ReactNode } from "react";
+  interface Props extends ComponentProps<"div"> {
+    children: ReactNode;
+    className?: string;
+  }
+  export default function Tabs(props: Props): JSX.Element;
+}
+
+declare module "@theme/TabItem" {
+  import type { ReactNode } from "react";
+  interface Props {
+    children: ReactNode;
+    value: string;
+    label?: ReactNode;
+    className?: string;
+    key?: string;
+  }
+  export default function TabItem(props: Props): JSX.Element;
+}