feat(i18n,rtl): full Arabic localization + RTL sweep across all layouts

Frontend
- i18n: install tailwindcss-rtl, Cairo font, RTL-aware direction in index.css.
- Language toggle: localize aria-label / menu label, persist choice, update
  document dir synchronously.
- Sidebar: add `side` prop so the drawer pins to the right in RTL; wire up
  AdminLmsLayout, RoleLayout (student/teacher) and AppSidebar to pass
  side = i18n.dir() === 'rtl' ? 'right' : 'left'.
- AdminLmsLayout: convert every nav item from hard-coded title to titleKey,
  translate group labels (incl. the collapsible Training), breadcrumbs,
  user menu (Profile / Settings / Logout), help button and toggle aria
  labels; replace physical mr-/right- utilities with logical me-/end-.
- AI components (AiTipBanner, AiInsightsPanel, AiAlertBanner, AiSearchBar,
  AiAssistantDrawer): apply dir="auto" at the container level, localize
  titles, loading / error / empty states.
- Dashboards (admin / student / teacher): wrap numeric values in <bdi>,
  localize dates via ar-EG, fix flex direction for KPI and assignment cards.
- UI primitives (breadcrumb, calendar, carousel, dropdown-menu, menubar,
  context-menu, pagination, sidebar): flip chevrons in RTL via a scoped
  CSS rule, swap pl-/pr-/ml-/mr- for ps-/pe-/ms-/me-.
- Add logical-direction helpers and bidirectional isolation classes.

Locales
- Expand en.ts and ar.ts with full `nav`, `sidebarGroup`, `breadcrumb`,
  `userMenu`, `chrome`, `ai`, and dashboard key sets; keep key parity.

API client
- `api-client.ts` reads the active language from localStorage/i18n and sends
  `Accept-Language` on every request so the backend can localize AI output.

Backend (encoach_ai)
- openai_service: add _LANGUAGE_NAMES, normalize_language, language-aware
  system prompt injection for every OpenAI call.
- coach_service + controllers (coach_controller, ai_controller): thread
  the requested language from headers / user locale down to OpenAIService.
- ai_feedback: fix latent registry error by pointing course_id at op.course
  instead of the non-existent encoach.course.

Other
- .gitignore: ignore runtime odoo logs and local caches.

Made-with: Cursor

src/components/TeacherLayout.tsx

@@ -1,39 +1,40 @@
 import RoleLayout, { NavGroup } from "./RoleLayout";
 import {
-  LayoutDashboard, BookOpen, ClipboardList, FileText,
+  LayoutDashboard, BookOpen, ClipboardList,
   CalendarCheck, Users, Calendar, User, MessageSquare,
-  Megaphone, Wand2, Library,
+  Megaphone, Library,
 } from "lucide-react";
 
+/** Teacher portal shell. See `StudentLayout` for the nav-config rationale. */
 const navGroups: NavGroup[] = [
   {
-    label: "Teaching",
+    labelKey: "sidebarGroup.teaching",
     items: [
-      { title: "Dashboard", url: "/teacher/dashboard", icon: LayoutDashboard },
-      { title: "Courses", url: "/teacher/courses", icon: BookOpen },
-      { title: "Resource Library", url: "/teacher/library", icon: Library },
-      { title: "Assignments", url: "/teacher/assignments", icon: ClipboardList },
+      { titleKey: "nav.dashboard", url: "/teacher/dashboard", icon: LayoutDashboard },
+      { titleKey: "nav.courses", url: "/teacher/courses", icon: BookOpen },
+      { titleKey: "nav.resourceLibrary", url: "/teacher/library", icon: Library },
+      { titleKey: "nav.assignments", url: "/teacher/assignments", icon: ClipboardList },
     ],
   },
   {
-    label: "Management",
+    labelKey: "sidebarGroup.management",
     items: [
-      { title: "Attendance", url: "/teacher/attendance", icon: CalendarCheck },
-      { title: "Students", url: "/teacher/students", icon: Users },
-      { title: "Timetable", url: "/teacher/timetable", icon: Calendar },
+      { titleKey: "nav.attendance", url: "/teacher/attendance", icon: CalendarCheck },
+      { titleKey: "nav.students", url: "/teacher/students", icon: Users },
+      { titleKey: "nav.timetable", url: "/teacher/timetable", icon: Calendar },
     ],
   },
   {
-    label: "Communication",
+    labelKey: "sidebarGroup.communication",
     items: [
-      { title: "Discussions", url: "/teacher/discussions", icon: MessageSquare },
-      { title: "Announcements", url: "/teacher/announcements", icon: Megaphone },
+      { titleKey: "nav.discussions", url: "/teacher/discussions", icon: MessageSquare },
+      { titleKey: "nav.announcements", url: "/teacher/announcements", icon: Megaphone },
     ],
   },
   {
-    label: "Account",
+    labelKey: "sidebarGroup.account",
     items: [
-      { title: "Profile", url: "/teacher/profile", icon: User },
+      { titleKey: "nav.profile", url: "/teacher/profile", icon: User },
     ],
   },
 ];