Show "Booked by" in the Account section of a student's detail page

The parent/guardian was only named further down under Profile, where it
reads as background rather than as an account fact, and only when there
was one — so a page with no such line was ambiguous between "books for
themselves" and "the lookup found nothing".

It now sits in the Account table beside display name and email, as the
guardian's name linked to their own detail page, and always renders: a
student who books for themselves says so outright. No email address —
theirs is one click away on their own page, and repeating it here only
makes the row harder to scan. The Profile section keeps only the note
explaining the placeholder email, which is a different point.

Tests: composer test (863), composer lint, composer cs all pass.

Co-Authored-By: Claude Opus 5 <[email protected]>

templates/admin/student-detail.php

@@ -114,6 +114,8 @@ $renderLessons = static function (array $rows, bool $withActions = false): void
         <div class="notice notice-error is-dismissible"><p><?php echo esc_html($error); ?></p></div>
     <?php endif; ?>
 
+    <?php $detailUrl = static fn(int $id): string => add_query_arg(['page' => $pageSlug, 'student_id' => $id], admin_url('admin.php')); ?>
+
     <h2><?php esc_html_e('Account', 'unsupervised-schedular'); ?></h2>
     <form method="post">
         <?php wp_nonce_field('usc_student_actions'); ?>
@@ -131,24 +133,32 @@ $renderLessons = static function (array $rows, bool $withActions = false): void
                 <th><?php esc_html_e('Registered', 'unsupervised-schedular'); ?></th>
                 <td><?php echo esc_html($student->user_registered); ?></td>
             </tr>
+            <?php
+            /*
+             * Always rendered, both ways round. "Books for themselves" is a fact
+             * worth stating outright: an empty row would be indistinguishable
+             * from a guardian the page failed to look up.
+             */
+            ?>
+            <tr>
+                <th><?php esc_html_e('Booked by', 'unsupervised-schedular'); ?></th>
+                <td>
+                    <?php if ($guardian !== null) : ?>
+                        <?php // The name alone. Their address is one click away on their own page, and repeating it here only makes the row harder to scan. ?>
+                        <a href="<?php echo esc_url($detailUrl($guardian['id'])); ?>"><?php echo esc_html($guardian['name']); ?></a>
+                    <?php else : ?>
+                        <span class="description"><?php esc_html_e('Nobody — this student books and pays for themselves.', 'unsupervised-schedular'); ?></span>
+                    <?php endif; ?>
+                </td>
+            </tr>
         </table>
         <?php submit_button(esc_html__('Save account details', 'unsupervised-schedular'), 'secondary', 'submit', false); ?>
     </form>
 
     <?php if ($guardian !== null || ! empty($children)) : ?>
         <h2><?php esc_html_e('Profile', 'unsupervised-schedular'); ?></h2>
-        <?php $detailUrl = static fn(int $id): string => add_query_arg(['page' => $pageSlug, 'student_id' => $id], admin_url('admin.php')); ?>
         <?php if ($guardian !== null) : ?>
-            <p>
-                <?php
-                printf(
-                    /* translators: 1: linked name of the parent/guardian, 2: their email address. */
-                    esc_html__('Books and pays through %1$s (%2$s).', 'unsupervised-schedular'),
-                    '<a href="' . esc_url($detailUrl($guardian['id'])) . '">' . esc_html($guardian['name']) . '</a>',
-                    esc_html($guardian['email'])
-                );
-                ?>
-            </p>
+            <?php // Who they book through is up in Account; this explains the placeholder email. ?>
             <p class="description"><?php esc_html_e('This is a managed student account: it has no login of its own, and its email address is a placeholder that cannot receive mail.', 'unsupervised-schedular'); ?></p>
         <?php endif; ?>
         <?php if (! empty($children)) : ?>