Refactor Site ID Verification to Use Admins Sites Table and Fix Broken Revert Feature by Replacing link_to Helper with button_to

[jaredblumer]

Description

This PR refactors site ID verification by replacing the site_id parameter check with a direct lookup in the admins_sites table, where user site access is stored.

Additionally, this pull request replaces the link_to helper with button_to in the Previous Versions partial to ensure the correct HTTP method is used. Previously, link_to began forcing a GET request, but button_to generates a form that submits a POST request with "_method"=>"put" that overrides the request method to PUT in Rails. To avoid the button forms conflicting with the main page form, the Previous Versions partial is now rendered outside of it.

This pull request also fixes a bug wherein the Save and Continue button was redirecting users to the Content page due to the Save and Continue button missing the site_id parameter. The site ID refactor resolves this issue.

Because the site ID verification within the edit page view no longer uses the site_id parameter, this was removed in the Content nodes and the Page Search nodes. The site_id parameter is still used when selecting a site from the multisite dropdown.

Testing

Site ID Verification

1. In the Admin panel, identify a site and open a page.
2. Copy the page's URL.
3. Navigate to Settings > Users and remove your user’s access to the selected site.
4. Attempt to visit the copied URL. You should be redirected to the content of a permitted site.

Page Version Revert

1. Open a page and make a change.
2. In the Previous Versions dropdown, select an earlier version.
3. The page should display the content from the selected previous version, reflecting how it appeared before your edits.

Save and Continue

1. Open a page and make a change.
2. Select Save and Continue.
3. You should be redirected back to the edit page view with your changes saved.