Feature: add locale support for visual form builder

[glaubersilva]

Resolves GIVE-2124

Description

This PR adds support for v3 forms to work with different locales through the use of multilingual plugins. As a bonus, it also allows the creation of new forms respecting the language selected in the WP admin bar through the selectors provided by the WPML and Polylang plugins.

How it's working?

Before, in the render() method of the BlockRenderController() class we are returning a div with some data attributes like data-form-url that are used in the frontend. Now we also are sending a new data-form-locale attribute to be used in the frontend for subsequent requests (donation-form-view, donation-form-view-preview, and donation-confirmation-receipt-view).

Why it works?

Because when the render() method of the BlockRenderController() class is triggered it has the right context of the selected locale, but the subsequent requests made to the server by the frontend (donation-form-view, donation-form-view-preview, and donation-confirmation-receipt-view) didn't have it before but now they have because the new locale attribute is passed alongside to the subsequent requests and retrieved back in the Give\Framework\Routes\Router class and then used in the views to make sure we are rendering them with the proper locale.

It was inspired by this feature from the Polylang Pro plugin: https://polylang.pro/doc/rest-api/

Affects

The v3 forms.

Visuals

V3 forms - multilingual plugins support

https://www.loom.com/share/99d359f094f4448194965d506ea937ef?sid=bddc70ff-5dee-48fd-a4a2-9b7345c1fbe7

[Bonus Feature] Creating new V3 forms respecting the language selected on the WPML language selector or Polylang Language selector

https://www.loom.com/share/bbd4328a2b2b409784dcce6d3ae3871d?sid=d9e31524-1437-4737-8e46-cfbf5a000ea4

Testing Instructions

V3 forms - multilingual plugins support

1. Install WPML or Polylang plugin;
2. Setup the plugin installed Previously to use two languages;
3. Create two v3 forms, one for each language setup previously;
4. Use Loco Translate to translate strings that can't be translated using the Visual Form Builder;
5. Create a new page for the Language 1 and insert the proper form shortcode on it;
6. Create a new page for the Language 2 and insert the proper form shortcode on it;
7. Access the page of the Language 1 and make sure everything is being displayed as expected;
8. Use the language selector provided by the plugin (on the frontend) to switch to the Language 2 page and make sure everything is being displayed as expected;

[Bonus Feature] Creating new V3 forms respecting the language selected on the WPML language selector or Polylang Language selector

1. Install WPML or Polylang plugin;
2. Setup the plugin installed Previously to use two languages;
3. Use Loco Translate to translate strings that can't be translated using the Visual Form Builder;
4. Go to the GiveWP > All Forms page;
5. Select the wished language in the language selector localized in the WP admin bar;
6. Click on "Add Form" and make sure the new form was created respecting the language selected previously.

Pre-review Checklist

• Acceptance criteria satisfied and marked in related issue
• Relevant @unreleased tags included in DocBlocks
• Includes unit tests
• Reviewed by the designer (if follows a design)
• Self Review of code and UX completed

[kjohnson]

@glaubersilva I think we can simplify this by moving the locale switching higher up the request chain in the places where we are passing the locale from Request to Controller to View Model.

[glaubersilva]

@kjohnson This is ready for re-review.

[kjohnson]

Looks like this broke a test:

Give\Tests\Unit\DonationForms\Endpoints\TestListDonationForms::testShouldReturnListWithSameData

+ 'edit' => '?locale=en_US'
- 'edit' => null

The edit link no longer matches. Was it previously null?

[glaubersilva]

@kjohnson The broken test was fixed here: 920f146

This is ready for re-review.

[kjohnson]

Build for QA, see https://github.com/impress-org/givewp/actions/runs/13293612151.

[rickalday]

Passed manual QA tests.