Add lessons module, rate cycles, EC2 deploy scripts, and help content

- Lessons module: lesson types, instructors, schedule slots, enrollments,
  sessions (list + week grid view), lesson plans, grading scales, templates
- Rate cycles: replace monthly_rate with billing_interval + billing_unit on
  enrollments; add weekly/monthly/quarterly rate presets to lesson types and
  schedule slots with auto-fill on enrollment form
- Member detail page: tabbed layout for details, identity documents, enrollments
- Sessions week view: custom 7-column grid replacing react-big-calendar
- Music store seed: instructors, lesson types, slots, enrollments, sessions,
  grading scale, lesson plan template
- Scrollbar styling: themed to match sidebar/app palette
- deploy/: EC2 setup and redeploy scripts, nginx config, systemd service
- Help: add Lessons category (overview, types, instructors, slots, enrollments,
  sessions, plans/grading); collapsible sidebar with independent scroll;
  remove POS/accounting references from docs

packages/admin/src/routes/_authenticated.tsx

@@ -8,7 +8,7 @@ import { myPermissionsOptions } from '@/api/rbac'
 import { moduleListOptions } from '@/api/modules'
 import { Avatar } from '@/components/shared/avatar-upload'
 import { Button } from '@/components/ui/button'
-import { Users, UserRound, HelpCircle, Shield, UserCog, LogOut, User, Wrench, Package, ClipboardList, FolderOpen, KeyRound, Settings, PanelLeftClose, PanelLeft } from 'lucide-react'
+import { Users, UserRound, HelpCircle, Shield, UserCog, LogOut, User, Wrench, Package, ClipboardList, FolderOpen, KeyRound, Settings, PanelLeftClose, PanelLeft, CalendarDays, GraduationCap, CalendarRange, BookOpen, BookMarked } from 'lucide-react'
 
 export const Route = createFileRoute('/_authenticated')({
   beforeLoad: () => {
@@ -142,6 +142,7 @@ function AuthenticatedLayout() {
 
   const canViewAccounts = !permissionsLoaded || hasPermission('accounts.view')
   const canViewRepairs = !permissionsLoaded || hasPermission('repairs.view')
+  const canViewLessons = !permissionsLoaded || hasPermission('lessons.view')
   const canViewUsers = !permissionsLoaded || hasPermission('users.view')
 
   const [collapsed, setCollapsed] = useState(false)
@@ -186,6 +187,17 @@ function AuthenticatedLayout() {
                 )}
               </NavGroup>
             )}
+            {isModuleEnabled('lessons') && canViewLessons && (
+              <NavGroup label="Lessons" collapsed={collapsed}>
+                <NavLink to="/lessons/schedule" icon={<CalendarDays className="h-4 w-4" />} label="Schedule" collapsed={collapsed} />
+                <NavLink to="/lessons/enrollments" icon={<GraduationCap className="h-4 w-4" />} label="Enrollments" collapsed={collapsed} />
+                <NavLink to="/lessons/sessions" icon={<CalendarRange className="h-4 w-4" />} label="Sessions" collapsed={collapsed} />
+                <NavLink to="/lessons/plans" icon={<BookOpen className="h-4 w-4" />} label="Lesson Plans" collapsed={collapsed} />
+                {hasPermission('lessons.admin') && (
+                  <NavLink to="/lessons/templates" icon={<BookMarked className="h-4 w-4" />} label="Templates" collapsed={collapsed} />
+                )}
+              </NavGroup>
+            )}
             {(isModuleEnabled('files') || isModuleEnabled('vault')) && (
               <NavGroup label="Storage" collapsed={collapsed}>
                 {isModuleEnabled('files') && (