Multiple bug fixes and feature additions

[Contents of the fix]
■Fixed a bug that sometimes prevented the setting of eye-catchers on Welcart product pages.
■Adjusted the display of Welcart product pages when using the block editor.
■Fixed an issue where the amount of money in the search results list was not displayed correctly when using the “Combined Product Category Search” in the “Welcart Keyword Search” widget.
■Fixed the site search function so that contents created with Page Builder are also searchable.
■Fixed a bug in which the preview did not work properly on pages using Page Builder.
■Added discount rate (discount amount) display setting to TCD Theme Options > Products > Display Settings > Article Detail Page Settings.

The following files have been modified for this update.
【Fixed files】
admin/inc/basic.php
admin/inc/welcart.php
admin/theme-options.php
functions/welcart_cf.php
languages/ja.mo
languages/ja.po
pagebuilder/assets/admin/css/admin.css
pagebuilder/assets/admin/js/admin.js
pagebuilder/assets/css/googlemap.css
pagebuilder/modules/includes/slick.php
pagebuilder/modules/slider.php
pagebuilder/pagebuilder.php
functions.php
style.css
wc_templates/wc_item_single.php
wc_templates/wc_search_page.php