feat: initial commit — asaas-checkout template white-label

Template genérico de checkout com ASAAS, parametrizado via env vars.
Inclui fluxo completo: checkout → pedido → polling → webhook → admin.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/auth-context.tsx

@@ -0,0 +1,48 @@
+"use client"
+
+import type React from "react"
+
+import { createContext, useContext, useState, useEffect } from "react"
+
+interface AuthContextType {
+  isLoggedIn: boolean
+  login: (username: string, password: string) => Promise<boolean>
+  logout: () => void
+}
+
+const AuthContext = createContext<AuthContextType>({
+  isLoggedIn: false,
+  login: async () => false,
+  logout: () => {},
+})
+
+export const useAuth = () => useContext(AuthContext)
+
+export const AuthProvider = ({ children }: { children: React.ReactNode }) => {
+  const [isLoggedIn, setIsLoggedIn] = useState(false)
+
+  useEffect(() => {
+    const token = localStorage.getItem("isLoggedIn")
+    if (token === "true") {
+      setIsLoggedIn(true)
+    }
+  }, [])
+
+  const login = async (username: string, password: string) => {
+    const adminUser = process.env.NEXT_PUBLIC_ADMIN_USER ?? "admin"
+    const adminPass = process.env.NEXT_PUBLIC_ADMIN_PASSWORD ?? "admin"
+    if (username === adminUser && password === adminPass) {
+      localStorage.setItem("isLoggedIn", "true")
+      setIsLoggedIn(true)
+      return true
+    }
+    return false
+  }
+
+  const logout = () => {
+    localStorage.removeItem("isLoggedIn")
+    setIsLoggedIn(false)
+  }
+
+  return <AuthContext.Provider value={{ isLoggedIn, login, logout }}>{children}</AuthContext.Provider>
+}