feat(backoffice): redesign backoffice UI dengan shadcn/ui

Menyeluruh merancang ulang apps/backoffice memakai pola shadcn/ui sambil
mempertahankan seluruh palette warna existing (primary/neutral/success/
info/warning/danger) dan typography Bai Jamjuree.

UI library (libs/ui):
- Atoms existing (Button, Input, Label, Textarea, Card, Dialog, Drawer,
  Form, Select, Toggle) dirombak ke pola shadcn, API dipertahankan agar
  sibling apps (gacha, dimentorin, hackathon, qrcampaign) tidak break
- Select atom beralih dari native ke Radix Select + NativeSelect fallback
- 18 atom baru: Badge, Avatar, Separator, Skeleton, Tabs, Tooltip,
  DropdownMenu, Popover, AlertDialog, Checkbox, RadioGroup, Switch,
  ScrollArea, Sheet, Sidebar, Breadcrumb, Table, + use-mobile hook
- DataTable, Filter, BackofficeWrapper, Pagination, Modal (alias Dialog)
  direstyle dengan token baru
- CSS variable layer shadcn ditambahkan (--color-primary, --color-sidebar-*,
  dll) dipetakan ke palette existing; tw-animate-css di-import untuk
  transisi

Backoffice shell:
- Sidebar bersarang SidebarProvider + SidebarInset, built-in mobile Sheet,
  user DropdownMenu (Avatar + logout), ikon lucide-react

Pages redesign (19 list/dashboard/settings):
- accounts, cms-events, cms-testimonials, dashboard, dashboard-dimentorin
  (dengan recharts di Card), feedback-review-dimentorin, gacha-roll,
  hackathon-dashboard, hackathon-submissions, hackathon-teams,
  hackathon-users, permissions, prizes, roadmap-dimentorin, roles,
  session-dimentorin, settings-dimentorin (Tabs), transactions,
  users-dimentorin (Tabs mentor/mentee)
- Pola unified: BackofficeWrapper > Card (CardHeader toolbar + CardContent
  DataTable) + AlertDialog untuk delete confirm
- Form accounts_/$id diredesign; form pages lain tetap pakai
  ControlledInputField yang sekarang berbasis shadcn Input

Dependencies:
- +20 radix-ui primitives, lucide-react, cmdk, input-otp
- Select native patched di dimentorin (profile-sidebar, schedule step)
  untuk tetap kompatibel via NativeSelect alias

Verifikasi:
- nx build backoffice: sukses (2.33s, 4801 modules)
- nx build dimentorin/gacha/hackathon/qrcampaign: semua sukses (zero
  regresi dari rewrite libs/ui)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/dimentorin/src/routes/_public/auth/register-mentor.tsx

@@ -1,7 +1,7 @@
 import { createFileRoute } from '@tanstack/react-router'
 import { FC, ReactElement, useState } from 'react'
 import { ControlledInputField, RegisterResetBanner } from '@imphnen-frontend-service/ui/organisms'
-import { Button, Select } from '@imphnen-frontend-service/ui/atoms'
+import { Button } from '@imphnen-frontend-service/ui/atoms'
 import { ArrowLeftOutlined, ArrowRightOutlined } from '@ant-design/icons'
 import { InputField, RegisterMentorStep, SelectField } from '@imphnen-frontend-service/ui/molecules'
 

apps/dimentorin/src/routes/_site/mentoring_/$id/_components/modals/appointment/steps/schedule.tsx

@@ -1,4 +1,4 @@
-import { Input, Select, Textarea } from "@imphnen-frontend-service/ui/atoms"
+import { Input, NativeSelect as Select, Textarea } from "@imphnen-frontend-service/ui/atoms"
 import { cn } from "@imphnen-frontend-service/utils"
 import { motion } from "framer-motion"
 

apps/dimentorin/src/routes/_site/profile_/_components/profile/profile-sidebar.tsx

@@ -1,5 +1,5 @@
 import { FC, useState, useEffect, useCallback } from 'react';
-import { Select } from '@imphnen-frontend-service/ui/atoms';
+import { NativeSelect as Select } from '@imphnen-frontend-service/ui/atoms';
 import { SectionWrapper } from '../shared/section-wrapper';
 import { NotificationType } from '../modals/notification-modal';
 import { PersonalInfoSection } from '../sections/personal-info-section';