Initial commit: Leopost Full — merge di Leopost, Post Generator e Autopilot OS

- Backend FastAPI con multi-LLM (Claude/OpenAI/Gemini)
- Publishing su Facebook, Instagram, YouTube, TikTok
- Calendario editoriale con awareness levels (PAS, AIDA, BAB...)
- Design system Editorial Fresh (Fraunces + DM Sans)
- Scheduler automatico, gestione commenti AI, affiliate links

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

frontend/src/AuthContext.jsx

@@ -0,0 +1,41 @@
+import { createContext, useContext, useState, useEffect } from 'react'
+import { api } from './api'
+
+const AuthContext = createContext(null)
+
+export function AuthProvider({ children }) {
+  const [user, setUser] = useState(null)
+  const [loading, setLoading] = useState(true)
+
+  useEffect(() => {
+    const token = localStorage.getItem('token')
+    if (token) {
+      api.get('/auth/me')
+        .then((data) => setUser(data))
+        .catch(() => localStorage.removeItem('token'))
+        .finally(() => setLoading(false))
+    } else {
+      setLoading(false)
+    }
+  }, [])
+
+  const login = async (username, password) => {
+    const data = await api.post('/auth/login', { username, password })
+    localStorage.setItem('token', data.access_token)
+    const me = await api.get('/auth/me')
+    setUser(me)
+  }
+
+  const logout = () => {
+    localStorage.removeItem('token')
+    setUser(null)
+  }
+
+  return (
+    <AuthContext.Provider value={{ user, loading, login, logout }}>
+      {children}
+    </AuthContext.Provider>
+  )
+}
+
+export const useAuth = () => useContext(AuthContext)