[BUG] Duplicate routes with embedded sidebar

[khannanov-nil]

Issue

The normal flow of configuring and using the plugin results in receiving the following error when using Docusaurus 3.x.

[WARNING] Duplicate routes found!
- Attempting to create page at \nil\reference\json-rpc-api, but a page already exists at this route.
This could lead to non-deterministic routing behavior.

As a result of this error, the entire site fails to render.

Steps to reproduce

docusaurus.config.js:

// @ts-check
// `@type` JSDoc annotations allow editor autocompletion and type checking
// (when paired with `@ts-check`).
// There are various equivalent ways to declare your Docusaurus config.
// See: https://docusaurus.io/docs/api/docusaurus-config

import { themes as prismThemes } from 'prism-react-renderer';

import remarkMath from 'remark-math';
import rehypeKatex from 'rehype-katex';

/** @type {import('@docusaurus/types').Config} */
const config = {
  title: '=nil; Foundation Documentation Portal',
  tagline: '',
  favicon: 'img/nil-logo.png',

  // Set the production url of your site here
  url: 'https://docs.nil.foundation/',
  // Set the /<baseUrl>/ pathname under which your site is served
  // For GitHub pages deployment, it is often '/<projectName>/'
  baseUrl: '/',

  // GitHub pages deployment config.
  // If you aren't using GitHub pages, you don't need these.
  organizationName: '=nil; Foundation', // Usually your GitHub org/user name.
  projectName: 'docs.nil.foundation', // Usually your repo name.

  onBrokenLinks: 'throw',
  onBrokenMarkdownLinks: 'warn',

  // Even if you don't use internationalization, you can use this field to set
  // useful metadata like html lang. For example, if your site is Chinese, you
  // may want to replace "en" with "zh-Hans".
  i18n: {
    defaultLocale: 'en',
    locales: ['en'],
  },

  presets: [
    [
      "@metamask/docusaurus-openrpc/dist/preset",
      /** @type {import('@metamask/docusaurus-openrpc/dist/preset').Options} */
      ({
        docs: {
          path: 'nil',
          routeBasePath: 'nil',
          sidebarPath: require.resolve("./sidebar-nil.js"),
          remarkPlugins: [remarkMath],
          rehypePlugins: [rehypeKatex],
          openrpc: {
            openrpcDocument: "https://metamask.github.io/api-specs/latest/openrpc.json",
            path: "reference",
            sidebarLabel: "JSON-RPC API",
          },
        },
        theme: {
          customCss: require.resolve("./src/css/custom.css"),
        },
      }),
    ],
  ],
  markdown: {
    mermaid: true,
  },
  themes: ['@docusaurus/theme-mermaid'],
  plugins: [
    [
      '@docusaurus/plugin-content-docs',
      {
        id: 'zkllvm',
        path: 'zkllvm',
        routeBasePath: 'zkllvm',
        sidebarPath: './sidebar-zkllvm.js'
      }
    ],
    [
      '@docusaurus/plugin-content-docs',
      {
        id: 'proof-market',
        path: 'proof-market',
        routeBasePath: 'proof-market',
        sidebarPath: './sidebar-proof-market.js'
      }
    ],
    [
      '@docusaurus/plugin-content-docs',
      {
        id: 'crypto3',
        path: 'crypto3',
        routeBasePath: 'crypto3',
        sidebarPath: './sidebar-crypto-3.js'
      }
    ],
  ],
  stylesheets: [
    {
      href: 'https://cdn.jsdelivr.net/npm/katex@0.13.24/dist/katex.min.css',
      type: 'text/css',
      integrity:
        'sha384-odtC+0UGzzFL/6PNoE8rX/SPcQDXBJ+uRepguP4QkPCm2LBxH3FA3y+fKSiJ+AmM',
      crossorigin: 'anonymous',
    },
  ],
  themeConfig:
    /** @type {import('@docusaurus/preset-classic').ThemeConfig} */
    (
      {
        algolia: {
          appId: 'KDQGY81FVN',
          apiKey: '8ad8d801f2775ff3cf8c4433dfe290e4',
          indexName: 'nil',
          contextualSearch: true,
          searchParameters: {},
          searchPagePath: 'search',
          insights: false,
        },
        colorMode: {
          defaultMode: 'dark',
          disableSwitch: true,

        },
        navbar: {
          title: '=nil; Foundation',
          logo: {
            src: 'img/nil-logo.png',
          },
          items: [
            {
              position: 'left',
              label: '=nil;',
              to: '/nil/intro'
            },
            {
              position: 'left',
              label: 'zkLLVM',
              to: '/zkllvm/overview/what-is-zkllvm'

            },
            {
              position: 'left',
              label: 'Proof Market',
              to: '/proof-market/intro'
            },
            {
              position: 'left',
              label: 'Crypto3',
              to: '/crypto3/intro'
            },
          ],
        },
        footer: {
          links: [
            {
              title: 'Community',
              items: [
                {
                  label: 'Discord',
                  to: 'https://discord.gg/KmTAEjbmM3'
                },
                {
                  label: 'GitHub',
                  to: 'https://github.com/nilfoundation'
                },
                {
                  label: 'Telegram',
                  to: 'https://t.me/nilfoundation'
                }
              ],
            }
          ],
          style: 'dark',
          copyright: `Copyright © ${new Date().getFullYear()} =nil; Foundation`,
        },
        prism: {
          defaultLanguage: 'clike',
          theme: prismThemes.vsDark,
          darkTheme: prismThemes.vsDark,
        },
      }),
};

export default config;

sidebar-nil.js:

export default {
    nil: [
        {
            type: 'category',
            label: 'Introduction',
            collapsed: false,
            collapsible: true,
            items: [
                {
                    type: 'doc',
                    label: 'Overview',
                    id: 'intro',
                },
                {
                    type: 'doc',
                    label: 'Thesis',
                    id: 'thesis'
                },
                {
                    type: 'doc',
                    label: 'Principles',
                    id: 'principles'
                }
            ]
        },
        {
            type: 'category',
            label: 'Core concepts',
            collapsed: false,
            collapsible: true,
            items: [
                {
                    type: 'doc',
                    label: 'Accounts',
                    id: 'core-concepts/accounts',
                },
                {
                    type: 'doc',
                    label: 'Transaction lifecycle',
                    id: 'core-concepts/transaction-lifecycle',
                },
                {
                    type: 'doc',
                    label: 'Shards and parallelized execution',
                    id: 'core-concepts/shards-parallel-execution',
                },
                {
                    type: 'doc',
                    label: 'Contract co-location',
                    id: 'core-concepts/contract-co-location',
                },
            ]
        },
        {
            type: 'category',
            label: 'Specification',
            collapsed: true,
            collapsible: true,
            items: [
                {
                    type: 'doc',
                    label: 'Finality',
                    id: 'specification/finality',
                },
                {
                    type: 'doc',
                    label: 'Data availability',
                    id: 'specification/data-availability',
                },
                {
                    type: 'doc',
                    label: 'Sequencing',
                    id: 'specification/sequencing',
                },
            ]
        },

        {
            type: "category",
            label: "Reference",
            link: { type: "generated-index" },
            items: [{ type: "autogenerated", dirName: "reference" }],
        },
    ]


}

File structure:

root
-- nil
    -- reference
        -- test.md

Expected behaviour

The flow for configuring and using the plugin does not cause route duplication.