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/account/api/account.svelte.ts

@@ -5,7 +5,8 @@ import type {
   CreateAccountWorkspaceRequest,
   DeleteAccountWorkspaceRequest,
   GetAccountUsageRequest,
-  ListAccountWorkspacesRequest
+  ListAccountWorkspacesRequest,
+  ViewAsStudentTokenRequest
 } from '../utils/types';
 import { BaseApiWithErrors, classroomio } from '$lib/utils/services/api';
 import { ZCreateWorkspace, type TCreateWorkspace } from '@cio/utils/validation/account';
@@ -29,6 +30,20 @@ class AccountApi extends BaseApiWithErrors {
     });
   }
 
+  /**
+   * Mint a short-lived login-link token for the current user. Used by the
+   * "View as student" handoff to auto-authenticate the teacher on the org domain.
+   * Returns the token, or undefined on failure.
+   */
+  async createViewAsStudentToken(): Promise<string | undefined> {
+    const result = await this.execute<ViewAsStudentTokenRequest>({
+      requestFn: () => classroomio.account['view-as-student-token'].$post(),
+      logContext: 'creating view-as-student token'
+    });
+
+    return result?.data.token;
+  }
+
   async loadUsage() {
     return this.execute<GetAccountUsageRequest>({
       requestFn: () => classroomio.account.usage.$get(),

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

@@ -4,6 +4,7 @@ export type ListAccountWorkspacesRequest = typeof classroomio.account.workspaces
 export type CreateAccountWorkspaceRequest = typeof classroomio.account.workspaces.$post;
 export type DeleteAccountWorkspaceRequest = (typeof classroomio.account.workspaces)[':workspaceId']['$delete'];
 export type GetAccountUsageRequest = typeof classroomio.account.usage.$get;
+export type ViewAsStudentTokenRequest = (typeof classroomio.account)['view-as-student-token']['$post'];
 
 type ListSuccess = Extract<InferResponseType<ListAccountWorkspacesRequest>, { success: true }>;
 type UsageSuccess = Extract<InferResponseType<GetAccountUsageRequest>, { success: true }>;