Initial plugin scaffold: lesson scheduling WordPress plugin

- Custom DB tables for availability slots and lesson bookings
- Instructor (wp-admin) and student (front-end) roles with custom capabilities
- REST API under us-scheduler/v1 for availability CRUD and booking
- [us_booking] and [us_student_login] shortcodes for student front end
- PHPUnit + Brain\Monkey unit test suite (29 tests)
- Gitea Actions CI: lint, PHPStan, tests on PHP 8.1/8.2/8.3, no-debug check
- Feature docs under docs/features/

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/Unit/Model/LessonTest.php

@@ -0,0 +1,68 @@
+<?php
+declare(strict_types=1);
+
+namespace Unsupervised\Schedular\Tests\Unit\Model;
+
+use Unsupervised\Schedular\Model\Lesson;
+use Unsupervised\Schedular\Tests\Unit\TestCase;
+
+class LessonTest extends TestCase
+{
+    public function testStatusConstants(): void
+    {
+        self::assertSame('pending', Lesson::STATUS_PENDING);
+        self::assertSame('confirmed', Lesson::STATUS_CONFIRMED);
+        self::assertSame('cancelled', Lesson::STATUS_CANCELLED);
+    }
+
+    public function testValidStatusesContainsAllThree(): void
+    {
+        self::assertContains(Lesson::STATUS_PENDING, Lesson::VALID_STATUSES);
+        self::assertContains(Lesson::STATUS_CONFIRMED, Lesson::VALID_STATUSES);
+        self::assertContains(Lesson::STATUS_CANCELLED, Lesson::VALID_STATUSES);
+        self::assertCount(3, Lesson::VALID_STATUSES);
+    }
+
+    public function testConstructorDefaults(): void
+    {
+        $lesson = new Lesson(slotId: 1, studentId: 2, instructorId: 3);
+
+        self::assertSame(Lesson::STATUS_PENDING, $lesson->status);
+        self::assertNull($lesson->notes);
+        self::assertNull($lesson->id);
+    }
+
+    public function testFromRowMapsCorrectly(): void
+    {
+        $row = (object) [
+            'id'            => '99',
+            'slot_id'       => '10',
+            'student_id'    => '20',
+            'instructor_id' => '30',
+            'status'        => 'confirmed',
+            'notes'         => 'Bring your guitar.',
+        ];
+
+        $lesson = Lesson::fromRow($row);
+
+        self::assertSame(99, $lesson->id);
+        self::assertSame(10, $lesson->slotId);
+        self::assertSame(20, $lesson->studentId);
+        self::assertSame(30, $lesson->instructorId);
+        self::assertSame('confirmed', $lesson->status);
+        self::assertSame('Bring your guitar.', $lesson->notes);
+    }
+
+    public function testToArrayContainsExpectedKeys(): void
+    {
+        $lesson = new Lesson(1, 2, 3, Lesson::STATUS_PENDING, 'Note', 5);
+        $arr    = $lesson->toArray();
+
+        self::assertArrayHasKey('id', $arr);
+        self::assertArrayHasKey('slot_id', $arr);
+        self::assertArrayHasKey('student_id', $arr);
+        self::assertArrayHasKey('instructor_id', $arr);
+        self::assertArrayHasKey('status', $arr);
+        self::assertArrayHasKey('notes', $arr);
+    }
+}