feat(perms): canRead/canEdit with ancestor walk + tests

packages/backend/src/tests/dbHelper.ts

@@ -1,8 +1,8 @@
 import { migrate } from 'drizzle-orm/better-sqlite3/migrator';
 import { resolve } from 'node:path';
 import { createDb, type Db } from '../db/client.js';
-import { users } from '../db/schema.js';
-import type { UserRow } from '../db/schema.js';
+import { users, lessons, lessonSubscriptions } from '../db/schema.js';
+import type { UserRow, LessonRow } from '../db/schema.js';
 
 export function makeTestDb(): { db: Db; close: () => void } {
   const { db, sqlite } = createDb(':memory:');
@@ -24,3 +24,24 @@ export async function createUserDirect(
   }).returning().all();
   return row!;
 }
+
+export async function createLessonOwnedBy(
+  db: Db,
+  ownerId: number,
+  init: { name?: string; parentId?: number | null; visibility?: 'private' | 'shared'; isCurated?: boolean; bidirectional?: boolean } = {}
+): Promise<LessonRow> {
+  const [row] = db.insert(lessons).values({
+    name: init.name ?? 'Test lesson',
+    parentId: init.parentId ?? null,
+    ownerId,
+    visibility: init.visibility ?? 'private',
+    isCurated: init.isCurated ?? false,
+    bidirectional: init.bidirectional ?? false,
+    position: 0,
+  }).returning().all();
+  return row!;
+}
+
+export async function subscribeUserToLesson(db: Db, userId: number, lessonId: number): Promise<void> {
+  db.insert(lessonSubscriptions).values({ userId, lessonId }).run();
+}