feat: HLS streaming, transcripts, agent course generation & landing-page course previews (#663)

New features:
- HLS video encoding/streaming (hls routes, hls-encoder) and a media
  transcripts pipeline (transcripts route + media-transcript queries)
- AI assistant chat vs. run model: agent-course-generation worker/queue,
  run-monitor pane, chat-changes card, content ask-ai bar
- Per-theme course-page previews across org landing-page themes (bold,
  classic, corporate, editorial, etc.) with a shared course token/component set
- View-as-student mode and login-link / link-invite invite flows

Refactor:
- Extract packages/core consolidating config (env, storage, dashboard-url),
  services and utils previously duplicated under apps/api/src/config
- Remove legacy agent service modules (chat-tools, chat-context,
  context-window, document, fetch-url, lesson-content)
- Relax Cross-Origin-Resource-Policy to allow cross-origin media embedding
- Add format script to tenant-router so turbo run format covers it

apps/dashboard/src/lib/features/course/utils/course-preview.ts

@@ -1,6 +1,7 @@
 import { goto } from '$app/navigation';
 import { resolve } from '$app/paths';
 import { snackbar } from '$features/ui/snackbar/store';
+import { accountApi } from '$features/account/api/account.svelte';
 
 interface OpenCoursePreviewOptions {
   courseId: string;
@@ -8,6 +9,11 @@ interface OpenCoursePreviewOptions {
   currentOrgDomain?: string;
 }
 
+interface ViewAsStudentOptions {
+  courseSlug?: string | null;
+  currentOrgDomain?: string;
+}
+
 /** Absolute URL for the org-site public course page (`/course/{slug}`). Client-only. */
 export function getPublicCoursePageUrl(courseSlug: string, currentOrgDomain = ''): string {
   if (typeof window === 'undefined') {
@@ -41,6 +47,45 @@ export function openCoursePreview({ courseId, courseSlug, currentOrgDomain = ''
   return true;
 }
 
+/**
+ * "View as student" handoff. Mints a short-lived login-link token for the current
+ * user and navigates to the org domain's `/api/auth/login-link`, which signs them in
+ * there (host-only session) and redirects to the course's student view.
+ *
+ * One flow for cloud and self-hosted: on cloud the tenant-router worker fronts
+ * `/api/auth/*`→API and `/course/*`→dashboard under the tenant host; on self-hosted the
+ * dashboard's own `hooks.server.ts` proxies `/api/auth/*` to the API. Either way the
+ * cookie lands on `currentOrgDomain` and the relative `redirect` resolves there.
+ */
+export async function viewAsStudent({ courseSlug, currentOrgDomain = '' }: ViewAsStudentOptions) {
+  if (typeof window === 'undefined') {
+    return false;
+  }
+
+  if (!courseSlug) {
+    snackbar.info('course.header.preview_missing_slug');
+
+    return false;
+  }
+
+  const token = await accountApi.createViewAsStudentToken();
+  if (!token) {
+    snackbar.error('snackbar.view_as_student.failed');
+
+    return false;
+  }
+
+  const origin = currentOrgDomain?.trim() || window.location.origin;
+  const loginLinkUrl = new URL('/api/auth/login-link', origin);
+  loginLinkUrl.searchParams.set('token', token);
+  loginLinkUrl.searchParams.set('redirect', `/course/${courseSlug}`);
+
+  // Cross-origin handoff — open in a new tab so the teacher keeps their dashboard.
+  window.open(loginLinkUrl.toString(), '_blank', 'noopener,noreferrer');
+
+  return true;
+}
+
 export async function copyPublicCoursePageUrl(courseSlug: string, currentOrgDomain = '') {
   const url = getPublicCoursePageUrl(courseSlug, currentOrgDomain);
 

apps/dashboard/src/lib/features/course/utils/marks-utils.ts

@@ -2,8 +2,6 @@ import type { CourseContentItem, CourseMembers } from '$features/course/utils/ty
 import type { Marks } from './types';
 import { ContentType } from '@cio/utils/constants/content';
 import Papa from 'papaparse';
-import autoTable from 'jspdf-autotable';
-import jsPDF from 'jspdf';
 
 /** Exercise information for display in marks table (linear, no lesson grouping) */
 export interface ExerciseInfo {
@@ -188,13 +186,18 @@ export function generateMarksCSV(
  * @param studentMarksByExerciseId Student marks by exercise
  * @param courseTitle Course title for filename and header
  */
-export function generateMarksPDF(
+export async function generateMarksPDF(
   students: CourseMembers,
   exercises: ExerciseInfo[],
   studentMarksByExerciseId: StudentMarksByExercise,
   courseTitle: string
-): void {
+): Promise<void> {
   try {
+    const [{ default: jsPDF }, { default: autoTable }] = await Promise.all([
+      import('jspdf'),
+      import('jspdf-autotable')
+    ]);
+
     const doc = new jsPDF({ orientation: 'landscape' });
     const head = [['Student', ...exercises.map((ex) => ex.title), 'Avg grade']];
 

apps/dashboard/src/lib/features/course/utils/public-course-mappers.ts

@@ -69,7 +69,9 @@ export function toPublicLessonView(lesson: Extract<PublicItem, { kind: 'lesson'
     title: lesson.title,
     sectionTitle: lesson.sectionTitle,
     body: lesson.body ?? '',
-    video: lesson.video,
+    // `lesson.video.hls` may be present on the wire from the public-course
+    // API but isn't in the older inferred type; spread through verbatim.
+    video: lesson.video as PublicLessonViewData['video'],
     isUnlocked: lesson.isUnlocked
   };
 }

apps/dashboard/src/lib/features/course/utils/types.ts

@@ -301,6 +301,8 @@ export type CourseMetadata = (NonNullable<ApiCourse['metadata']> extends object
   ? NonNullable<ApiCourse['metadata']>
   : Record<string, unknown>) & {
   isContentGroupingEnabled?: boolean;
+  skills?: string[];
+  tools?: string[];
 };
 export type CourseCertificate =
   NonNullable<ApiCourse['certificate']> extends object