fix(setup-wizard): use deterministic /network/ URL on multisite setup success

inc/admin-pages/class-multisite-setup-admin-page.php

@@ -96,7 +96,7 @@
 	 * @return string Title of the page.
 	 */
 	public function get_title(): string {
 		return __('Enable WordPress Multisite', 'multisite-ultimate');
 	}
 
 	/**
@@ -106,7 +106,7 @@
 	 * @return string Menu label of the page.
 	 */
 	public function get_menu_title() {
 		return __('Multisite Ultimate', 'multisite-ultimate');
 	}
 
 	/**
@@ -129,22 +129,22 @@
 
 		return [
 			'welcome'   => [
 				'title'      => __('Multisite Required', 'multisite-ultimate'),
 				'next_label' => __('Get Started →', 'multisite-ultimate'),
 				'back'       => false,
 				'view'       => [$this, 'section_welcome'],
 			],
 			'configure' => [
 				'title'       => __('Network Configuration', 'multisite-ultimate'),
 				'description' => __('Configure your network settings. These settings determine how your sites will be structured.', 'multisite-ultimate'),
 				'next_label'  => __('Continue →', 'multisite-ultimate'),
 				'handler'     => [$this, 'handle_configure'],
 				'fields'      => [$this, 'get_network_configuration_fields'],
 				'back'        => true,
 			],
 			'install'   => [
 				'title'        => __('Installing Network', 'multisite-ultimate'),
 				'description'  => __('Setting up your WordPress Multisite network...', 'multisite-ultimate'),
 				'next_label'   => Core_Installer::get_instance()->all_done() ? __('Begin Ultimate Multisite Setup →', 'ultimate-multisite') : __('Install', 'ultimate-multisite'),
 				'disable_next' => true,
 				'handler'      => [$this, 'handle_install_complete'],
@@ -157,7 +157,7 @@
 				],
 			],
 			'complete'  => [
 				'title'       => __('Setup Complete', 'multisite-ultimate'),
 				'description' => __('WordPress Multisite setup is now complete!', 'multisite-ultimate'),
 				'view'        => [$this, 'section_complete'],
 				'back'        => false,
@@ -340,6 +340,11 @@
 		$result = wu_request('result', ''); // phpcs:ignore WordPress.Security.NonceVerification.Recommended
 
 		if ('success' === $result || is_multisite()) :
+			/*
+			 * Build the network-admin URL deterministically.
+			 *
+			 */
+			$continue_url = site_url('wp-admin/network/admin.php?page=wp-ultimo-setup');
 			?>
 		<div class="wu-bg-green-100 wu-border wu-border-green-300 wu-rounded-lg wu-p-4 wu-mb-6">
 			<div class="wu-flex">
@@ -358,7 +363,7 @@
 		</div>
 
 		<div class="wu-flex wu-justify-center">
-			<a href="<?php echo esc_url(wu_network_admin_url('wp-ultimo-setup')); ?>" class="button button-primary button-large">
+			<a href="<?php echo esc_url($continue_url); ?>" class="button button-primary button-large">
 				<?php esc_html_e('Continue to Multisite Ultimate Setup', 'multisite-ultimate'); ?>
 			</a>
 		</div>

tests/WP_Ultimo/Admin_Pages/Multisite_Setup_Admin_Page_Test.php

@@ -678,6 +678,39 @@ public function test_section_complete_button_uses_wp_button_classes_not_missing_
 		$this->assertStringNotContainsString('wu-bg-blue-700', $output, 'wu-bg-blue-700 is not in framework.css and must not be used');
 	}
 
+	/**
+	 * section_complete() Continue button must point at the /network/ admin URL.
+	 *
+	 * Regression: previously the button used wu_network_admin_url() which falls back
+	 * to admin_url() when is_multisite() returns false (e.g. when OPcache is still
+	 * serving a stale wp-config.php after the install step writes the MULTISITE
+	 * constant). That caused the success-page button to send users to
+	 * /wp-admin/admin.php?page=wp-ultimo-setup (single-site) instead of
+	 * /wp-admin/network/admin.php?page=wp-ultimo-setup. The fix builds the URL
+	 * deterministically with site_url(), so the path must always contain /network/.
+	 */
+	public function test_section_complete_continue_button_points_at_network_admin(): void {
+
+		$_GET['result'] = 'success';
+
+		ob_start();
+		$this->page->section_complete();
+		$output = ob_get_clean();
+
+		unset($_GET['result']);
+
+		$this->assertMatchesRegularExpression(
+			'#href="[^"]*/wp-admin/network/admin\.php\?page=wp-ultimo-setup[^"]*"#',
+			$output,
+			'Continue button must link to the network admin URL, not the single-site admin URL'
+		);
+		$this->assertDoesNotMatchRegularExpression(
+			'#href="[^"]*/wp-admin/admin\.php\?page=wp-ultimo-setup[^"]*"#',
+			$output,
+			'Continue button must NOT link to the single-site admin URL'
+		);
+	}
+
 	// -------------------------------------------------------------------------
 	// display_manual_instructions() — via reflection
 	// -------------------------------------------------------------------------