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

frontend/src/components/ui/breadcrumb.tsx

@@ -60,7 +60,12 @@ const BreadcrumbPage = React.forwardRef<HTMLSpanElement, React.ComponentPropsWit
 BreadcrumbPage.displayName = "BreadcrumbPage";
 
 const BreadcrumbSeparator = ({ children, className, ...props }: React.ComponentProps<"li">) => (
-  <li role="presentation" aria-hidden="true" className={cn("[&>svg]:size-3.5", className)} {...props}>
+  <li
+    role="presentation"
+    aria-hidden="true"
+    className={cn("[&>svg]:size-3.5 rtl:[&>svg]:rotate-180", className)}
+    {...props}
+  >
     {children ?? <ChevronRight />}
   </li>
 );