fix: Add parent product material inheritance for variations

[devbodaghe]

Description

This PR fixes an inconsistency in how product material attributes are handled for variable products in the Facebook for WooCommerce sync process. Previously, variations would not inherit their parent product's material attribute, unlike other attributes such as color and size.

What Changed

• Added parent fallback logic to get_fb_material() method
• Variations now check parent product's material value if no variation-specific material is set
• Maintains existing string sanitization and length limits

Before

// Only checked variation attributes and direct meta
$fb_material = get_post_meta($this->id, self::FB_MATERIAL, true);

After

// Now includes parent fallback like other attributes
if (empty($fb_material) && $this->is_type('variation')) {
    $parent_id = $this->get_parent_id();
    if ($parent_id) {
        $fb_material = get_post_meta($parent_id, self::FB_MATERIAL, true);
    }
}

Testing

1. Create a variable product with a material set at the parent level
2. Create variations without specific material values
3. Verify variations inherit the parent's material when syncing to Facebook
4. Verify variations with their own material values still use their specific value

Related Issues

• Fixes inconsistent material attribute syncing for variable products
• Aligns material handling with other product attributes

[facebook-github-bot]

@devbodaghe has imported this pull request. If you are a Meta employee, you can view this diff on Phabricator.

[facebook-github-bot]

@devbodaghe merged this pull request in d786cdd.