feat: live class sessions, CE workflow, and docs (#683)

Adds live-class session scheduling on lessons (join link, date/time,
timezone) with automatic 24h and 1h reminder emails plus a calendar
invite (.ics), a time-change notification with an updated invite, a
teacher-authored welcome email and session invite on enrollment, and a
"Notify students" quiz nudge.

LMS gets an upcoming live-sessions card and Join buttons, plus a
reusable live-session card component (3 states) in @cio/ui with a
Storybook story. The sidebar content tree now reflects sequential
progression locking like the content list, and the course-completion
confetti regression is fixed.

Org-based emails no longer reference ClassroomIO by name. Docs add
live-class, welcome-email, and course-progression guides, expand the
certificates guide (design, signatures, corrected labels), move
plan-required callouts to the top, flatten how-to-guides to the docs
root with redirects, and add screenshots. Includes an add-docs-image
skill.

packages/db/src/queries/newsfeed/newsfeed.ts

@@ -2,6 +2,7 @@ import * as schema from '@db/schema';
 
 import type { TCourseNewsfeed, TCourseNewsfeedComment, TNewCourseNewsfeed, TNewCourseNewsfeedComment } from '@db/types';
 import { and, db, desc, eq, lt, ne, sql } from '@db/drizzle';
+import { ROLE } from '@cio/utils/constants';
 
 /**
  * Gets newsfeed items by course ID
@@ -400,6 +401,8 @@ export async function getNewsfeedForEmail(
   organization: {
     name: string | null;
     siteName: string | null;
+    avatarUrl: string | null;
+    theme: string | null;
   } | null;
   courseMembers: Array<{
     email: string | null;
@@ -431,7 +434,7 @@ export async function getNewsfeedForEmail(
     const row = result[0];
 
     // Get all course members (excluding author if specified)
-    const memberConditions = [eq(schema.course.id, row.course.id)];
+    const memberConditions = [eq(schema.course.id, row.course.id), eq(schema.groupmember.roleId, ROLE.STUDENT)];
     if (excludeAuthorId) {
       memberConditions.push(ne(schema.groupmember.id, excludeAuthorId));
     }
@@ -460,7 +463,9 @@ export async function getNewsfeedForEmail(
         : null,
       organization: {
         name: row.organization.name,
-        siteName: row.organization.siteName
+        siteName: row.organization.siteName,
+        avatarUrl: row.organization.avatarUrl,
+        theme: row.organization.theme
       },
       courseMembers: membersResult
         .filter((m) => m.profile?.email) // Only include members with email