feat(instructor): add curriculum teaching view

CurriculumView.jsx — a new 'Curriculum' tab in the admin portal:
program structure (courses -> modules -> activities), mapped scenarios/
assessments, estimated teaching time, and instructor notes rendered per
activity. A student_id lookup shows one student's real per-activity
progress alongside the same structure, for spotting where someone is
stuck. Read-only, no WYSIWYG editor — course/module authoring stays
Git/migration-based this phase per docs/COURSE_CONTENT_MODEL.md.

Co-Authored-By: Claude Sonnet 5 <[email protected]>

frontend/src/admin/AdminPortal.jsx

@@ -11,6 +11,7 @@ import AssessmentsView from './AssessmentsView'
 import ClassroomView from './ClassroomView'
 import ProgramsView from './ProgramsView'
 import NotificationsView from './NotificationsView'
+import CurriculumView from './CurriculumView'
 import styles from './Admin.module.css'
 
 // Instructor/Admin portal — clearly separate from the student experience (/admin route,
@@ -24,6 +25,7 @@ const NAV = [
   { key: 'cohorts', label: 'Cohorts' },
   { key: 'students', label: 'Students' },
   { key: 'programs', label: 'Programs' },
+  { key: 'curriculum', label: 'Curriculum' },
   { key: 'classroom', label: 'Classroom' },
   { key: 'learning', label: 'Learning' },
   { key: 'assessments', label: 'Assessments' },
@@ -66,6 +68,7 @@ export default function AdminPortal() {
         {view === 'cohorts' && <CohortsView role={instructor.role} />}
         {view === 'students' && <StudentsView role={instructor.role} />}
         {view === 'programs' && <ProgramsView role={instructor.role} />}
+        {view === 'curriculum' && <CurriculumView />}
         {view === 'classroom' && <ClassroomView />}
         {view === 'learning' && <LearningView />}
         {view === 'assessments' && <AssessmentsView role={instructor.role} />}