[CLAUDE] Phase1: foundation - BE Clean Arch + Identity + JWT + 2 FE React + login E2E

Backend (.NET 10):
- Domain: BaseEntity/AuditableEntity, ContractType/Phase/ApprovalDecision enums, User/Role (Identity<Guid>), AppRoles (12 const)
- Application: IApplicationDbContext/ICurrentUser/IDateTime/IJwtTokenService, custom exceptions, ValidationBehavior (MediatR pipeline), Auth CQRS (Login/Refresh/Me), DependencyInjection
- Infrastructure: ApplicationDbContext (IdentityDbContext), AuditingInterceptor (auto audit + soft delete), DbInitializer (seed 12 role + admin), DesignTimeDbContextFactory, JwtTokenService, DateTimeService, DI
- Api: CurrentUserService, GlobalExceptionMiddleware (ProblemDetails), AuthController, Program.cs rewrite (Serilog + JWT + CORS + Swagger), appsettings + launchSettings (port 5443)
- Migration Init applied to SolutionErp_Dev LocalDB

Frontend (React 19 + Vite 8 + Tailwind 4):
- fe-admin (:8082 blue) + fe-user (:8080 emerald) - shared structure, khac menu + brand color
- Tailwind 4 via @tailwindcss/vite plugin, theme brand colors
- AuthContext (localStorage token), ProtectedRoute, Layout (sidebar + header)
- UI kit: Button/Input/Label (CVA + Tailwind)
- LoginPage voi toast error, DashboardPage/InboxPage placeholder
- Axios interceptor: auto Bearer + 401 redirect
- TanStack Query client, React Router 7, Sonner toast

Package downgrades (do .NET 10 / TS 6 compat):
- MediatR 14 -> 12.4.1 (v14 breaking changes)
- Swashbuckle 10 -> 6.9.0 (v10 khong tuong thich OpenApi 2)
- Removed Microsoft.AspNetCore.OpenApi (conflict voi Swashbuckle)

E2E verified: POST /api/auth/login qua Vite proxy ca 2 FE -> JWT + user info

Credentials seed: admin@solutionerp.local / Admin@123456

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

fe-user/src/pages/LoginPage.tsx

@@ -0,0 +1,73 @@
+import { useState, type FormEvent } from 'react'
+import { useNavigate, useLocation } from 'react-router-dom'
+import { toast } from 'sonner'
+import { Button } from '@/components/ui/Button'
+import { Input } from '@/components/ui/Input'
+import { Label } from '@/components/ui/Label'
+import { useAuth } from '@/contexts/AuthContext'
+import axios from 'axios'
+
+export function LoginPage() {
+  const { login } = useAuth()
+  const navigate = useNavigate()
+  const location = useLocation()
+  const [email, setEmail] = useState('admin@solutionerp.local')
+  const [password, setPassword] = useState('Admin@123456')
+  const [isSubmitting, setIsSubmitting] = useState(false)
+
+  async function handleSubmit(e: FormEvent<HTMLFormElement>) {
+    e.preventDefault()
+    setIsSubmitting(true)
+    try {
+      await login({ email, password })
+      const redirectTo = (location.state as { from?: { pathname: string } } | null)?.from?.pathname ?? '/inbox'
+      navigate(redirectTo, { replace: true })
+      toast.success('Đăng nhập thành công')
+    } catch (err) {
+      const msg = axios.isAxiosError(err)
+        ? err.response?.data?.detail ?? err.response?.data?.title ?? err.message
+        : 'Lỗi kết nối máy chủ'
+      toast.error(`Đăng nhập thất bại: ${msg}`)
+    } finally {
+      setIsSubmitting(false)
+    }
+  }
+
+  return (
+    <div className="flex min-h-screen items-center justify-center bg-slate-100 px-4">
+      <div className="w-full max-w-md rounded-lg border border-slate-200 bg-white p-8 shadow-sm">
+        <div className="mb-6 text-center">
+          <h1 className="text-2xl font-bold text-brand-700">SOLUTION ERP</h1>
+          <p className="mt-1 text-sm text-slate-500">Quản lý hợp đồng nhà cung cấp</p>
+        </div>
+        <form onSubmit={handleSubmit} className="space-y-4">
+          <div className="space-y-1.5">
+            <Label htmlFor="email">Email</Label>
+            <Input
+              id="email"
+              type="email"
+              value={email}
+              onChange={e => setEmail(e.target.value)}
+              autoComplete="email"
+              required
+            />
+          </div>
+          <div className="space-y-1.5">
+            <Label htmlFor="password">Mật khẩu</Label>
+            <Input
+              id="password"
+              type="password"
+              value={password}
+              onChange={e => setPassword(e.target.value)}
+              autoComplete="current-password"
+              required
+            />
+          </div>
+          <Button type="submit" className="w-full" disabled={isSubmitting}>
+            {isSubmitting ? 'Đang đăng nhập…' : 'Đăng nhập'}
+          </Button>
+        </form>
+      </div>
+    </div>
+  )
+}