chore: reorganize docs apps (#7228)

* reorganize docs apps

* add README

* fix directory

* add condition for old docs

www/apps/book/utils/sidebar-attach-common-options.mjs

@@ -0,0 +1,18 @@
+/** @type {Partial<import("../providers").SidebarItemType>} */
+const commonOptions = {
+  loaded: true,
+  isPathHref: true,
+}
+
+/**
+ *
+ * @param {import("../providers").SidebarItemType[]} sidebar
+ * @returns {import("../providers").SidebarItemType[]}
+ */
+export function sidebarAttachHrefCommonOptions(sidebar) {
+  return sidebar.map((item) => ({
+    ...commonOptions,
+    ...item,
+    children: sidebarAttachHrefCommonOptions(item.children || []),
+  }))
+}