doc: Kconfig: Add permalink to kconfig search

- kconfig_ext_paths: A list of base paths where to search for external modules

  Kconfig files when they use ``kconfig-ext: True``. The extension will look for

  ${BASE_PATH}/modules/${MODULE_NAME}/Kconfig.

- kconfig_gh_link_base_url: The base URL for the GitHub links. This is used to

  generate links to the Kconfig files on GitHub.

- kconfig_zephyr_version: The Zephyr version. This is used to generate links to

  the Kconfig files on GitHub.

"""

import argparse

        kconfig_db_file = outdir / "kconfig.json"

        kconfig_db = {

            "gh_base_url": app.config.kconfig_gh_link_base_url,

            "zephyr_version": app.config.kconfig_zephyr_version,

            "symbols": db,

        }

        with open(kconfig_db_file, "w") as f:

            json.dump(db, f)

            json.dump(kconfig_db, f)

    app.config.html_extra_path.append(kconfig_db_file.as_posix())

    app.config.html_static_path.append(RESOURCES_DIR.as_posix())

def setup(app: Sphinx):

    app.add_config_value("kconfig_generate_db", False, "env")

    app.add_config_value("kconfig_ext_paths", [], "env")

    app.add_config_value("kconfig_gh_link_base_url", "", "")

    app.add_config_value("kconfig_zephyr_version", "", "")

    app.add_node(

        KconfigSearchNode,

const DB_FILE = 'kconfig.json';

const RESULTS_PER_PAGE_OPTIONS = [10, 25, 50];

let zephyr_gh_base_url;

let zephyr_version;

/* search state */

let db;

    p.appendChild(pText);

}

/**

 * Generate a GitHub link for a given file path in the Zephyr repository.

 * @param {string} path - The file path in the repository.

 * @param {number} [line] - Optional line number to link to.

 * @param {string} [mode=blob] - The mode (blob or edit). Defaults to 'blob'.

 * @param {string} [revision=main] - The branch, tag, or commit hash. Defaults to 'main'.

 * @returns {string} - The generated GitHub URL.

 */

function getGithubLink(path, line, mode = "blob", revision = "main") {

    let url = [

        zephyr_gh_base_url,

        mode,

        revision,

        path

    ].join("/");

    if (line !== undefined){

        url +=  `#L${line}`;

    }

    return url;

}

/**

 * Render a Kconfig literal property.

 * @param {Element} parent Parent element.

 * @param {String} title Title.

 * @param {String} content Content.

 * @param {Element} contentElement Content Element.

 */

function renderKconfigPropLiteral(parent, title, content) {

function renderKconfigPropLiteralElement(parent, title, contentElement)

{

    const term = document.createElement('dt');

    parent.appendChild(term);

    literal.className = 'pre';

    code.appendChild(literal);

    const literalText = document.createTextNode(content);

    literal.appendChild(literalText);

    literal.appendChild(contentElement);

}

/**

 * Render a Kconfig literal property.

 * @param {Element} parent Parent element.

 * @param {String} title Title.

 * @param {String} content Content.

 */

function renderKconfigPropLiteral(parent, title, content) {

    const contentElement = document.createTextNode(content);

    renderKconfigPropLiteralElement(parent, title, contentElement);

}

/**

    renderKconfigPropList(props, 'Implied by', entry.implied_by, true);

    renderKconfigPropList(props, 'Ranges', entry.ranges, false);

    renderKconfigPropList(props, 'Choices', entry.choices, false);

    renderKconfigPropLiteral(props, 'Location', `${entry.filename}:${entry.linenr}`);

    /* symbol location with permalink */

    const locationPermalink = document.createElement('a');

    locationPermalink.href = getGithubLink(entry.filename, entry.linenr, "blob", zephyr_version);

    const locationElement = document.createTextNode(`${entry.filename}:${entry.linenr}`);

    locationElement.class = "pre";

    locationPermalink.appendChild(locationElement);

    renderKconfigPropLiteralElement(props, 'Location', locationPermalink);

    renderKconfigPropLiteral(props, 'Menu path', entry.menupath);

    return container;

    fetch(DB_FILE)

        .then(response => response.json())

        .then(json => {

            db = json;

            db = json["symbols"];

            zephyr_gh_base_url = json["gh_base_url"];

            zephyr_version = json["zephyr_version"];

            results.replaceChildren();

kconfig_generate_db = True

kconfig_ext_paths = [ZEPHYR_BASE]

kconfig_gh_link_base_url = "https://github.com/zephyrproject-rtos/zephyr"

kconfig_zephyr_version = f"v{version}" if is_release else "main"

# -- Options for zephyr.external_content ----------------------------------