Add lesson comments (Stage 6)

- LessonComment CRUD: addComment / deleteComment server actions
- LessonComments client component with form, avatar, delete
- Comments section at bottom of lesson page (enrolled users only)
- Soft-delete support, moderation for curator/admin
- ROADMAP: moved Квизы to end (Stage 11), marked Stage 7 done

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

src/app/(student)/courses/[slug]/lessons/[lessonId]/comment-actions.ts

@@ -0,0 +1,62 @@
+"use server";
+
+import { headers } from "next/headers";
+import { auth } from "@/lib/auth";
+import { prisma } from "@/lib/prisma";
+import { revalidatePath } from "next/cache";
+
+export async function addComment(lessonId: string, slug: string, text: string) {
+  const session = await auth.api.getSession({ headers: await headers() });
+  if (!session) throw new Error("Unauthorized");
+
+  const trimmed = text.trim();
+  if (!trimmed || trimmed.length > 2000) throw new Error("Invalid text");
+
+  // Verify user has access to this lesson's course
+  const lesson = await prisma.lesson.findUnique({
+    where: { id: lessonId },
+    select: { module: { select: { course: { select: { id: true } } } } },
+  });
+  if (!lesson) throw new Error("Lesson not found");
+
+  const isAdmin = session.user.role === "admin";
+  if (!isAdmin) {
+    const enrollment = await prisma.courseEnrollment.findUnique({
+      where: {
+        userId_courseId: {
+          userId: session.user.id,
+          courseId: lesson.module.course.id,
+        },
+      },
+    });
+    if (!enrollment) throw new Error("Not enrolled");
+    if (enrollment.expiresAt && enrollment.expiresAt < new Date()) throw new Error("Access expired");
+  }
+
+  await prisma.lessonComment.create({
+    data: { lessonId, userId: session.user.id, text: trimmed },
+  });
+
+  revalidatePath(`/courses/${slug}/lessons/${lessonId}`);
+}
+
+export async function deleteComment(commentId: string, lessonId: string, slug: string) {
+  const session = await auth.api.getSession({ headers: await headers() });
+  if (!session) throw new Error("Unauthorized");
+
+  const comment = await prisma.lessonComment.findUnique({ where: { id: commentId } });
+  if (!comment) throw new Error("Not found");
+
+  const canDelete =
+    comment.userId === session.user.id ||
+    session.user.role === "curator" ||
+    session.user.role === "admin";
+  if (!canDelete) throw new Error("Forbidden");
+
+  await prisma.lessonComment.update({
+    where: { id: commentId },
+    data: { deleted: true },
+  });
+
+  revalidatePath(`/courses/${slug}/lessons/${lessonId}`);
+}

src/app/(student)/courses/[slug]/lessons/[lessonId]/page.tsx

@@ -7,6 +7,7 @@ import { KinescopePlayer } from "@/components/player/kinescope-player";
 import { LessonContent } from "@/components/student/lesson-content";
 import { LessonCompleteButton } from "@/components/student/lesson-complete-button";
 import { HomeworkSection } from "@/components/student/homework-section";
+import { LessonComments } from "@/components/student/lesson-comments";
 
 interface Props {
   params: Promise<{ slug: string; lessonId: string }>;
@@ -18,7 +19,7 @@ export default async function LessonPage({ params }: Props) {
   const session = await auth.api.getSession({ headers: await headers() });
   const isAdmin = session?.user.role === "admin";
 
-  const [lesson, progress] = await Promise.all([
+  const [lesson, progress, comments] = await Promise.all([
     prisma.lesson.findUnique({
       where: { id: lessonId, ...(isAdmin ? {} : { published: true }) },
       include: {
@@ -49,6 +50,11 @@ export default async function LessonPage({ params }: Props) {
           where: { userId_lessonId: { userId: session.user.id, lessonId } },
         })
       : null,
+    prisma.lessonComment.findMany({
+      where: { lessonId },
+      orderBy: { createdAt: "asc" },
+      include: { user: { select: { id: true, name: true } } },
+    }),
   ]);
 
   // Fetch homework submission for this student
@@ -179,6 +185,25 @@ export default async function LessonPage({ params }: Props) {
           </div>
         )}
       </div>
+
+      {/* Comments */}
+      {session && (
+        <div
+          className="mt-10 pt-8"
+          style={{ borderTop: "2px solid var(--border)" }}
+        >
+          <p className="text-xs font-bold uppercase tracking-widest mb-6" style={{ color: "var(--muted-foreground)" }}>
+            Обсуждение ({comments.filter((c) => !c.deleted).length})
+          </p>
+          <LessonComments
+            lessonId={lessonId}
+            slug={slug}
+            comments={comments}
+            currentUserId={session.user.id}
+            currentUserRole={session.user.role ?? "student"}
+          />
+        </div>
+      )}
     </article>
   );
 }