feat(sprint1-step4): SuperOAuth login frontend

- AuthContext : fix exports, x-auth-token header, loginWithOAuth(), suppression axios/jwt-decode
- Login.jsx : redirect SuperOAuth Discord avec tenantId=clickerz
- AuthCallback.jsx : extraction token query param, flow OAuth complet
- .env.sample : ajout VITE_SUPEROAUTH_URL
- Mode invité préservé (pas de route guard)

Frontend/src/context/AuthContext.jsx

@@ -6,28 +6,34 @@ import React, {
     useEffect,
   } from "react";
   import PropTypes from "prop-types";
-  import axios from "axios";
-  import { jwtDecode } from "jwt-decode";
-  
+  const decodeJwtPayload = (token) =>
+    JSON.parse(atob(token.split(".")[1]));
+
   const AuthContext = createContext();
-  
+
   const AuthProvider = ({ children }) => {
     const [user, setUser] = useState(null);
     const [loading, setLoading] = useState(true);
-  
+
     useEffect(() => {
       const fetchData = async () => {
         const jwtToken = localStorage.getItem("token");
-  
+
         if (jwtToken) {
           try {
-            const decodedPayload = jwtDecode(jwtToken);
-            const res = await axios.get(
-              `${import.meta.env.VITE_BACKEND_URL}/api/users/${decodedPayload.user}`
+            const decodedPayload = decodeJwtPayload(jwtToken);
+            const res = await fetch(
+              `${import.meta.env.VITE_BACKEND_URL}/api/users/${decodedPayload.user}`,
+              {
+                headers: { "x-auth-token": jwtToken },
+              }
             );
-            setUser(res.data);
+            if (!res.ok) throw new Error("Failed to fetch user");
+            const data = await res.json();
+            setUser(data);
           } catch (error) {
             console.error("Error fetching user data:", error);
+            localStorage.removeItem("token");
           } finally {
             setLoading(false);
           }
@@ -35,15 +41,30 @@ import React, {
           setLoading(false);
         }
       };
-  
+
       fetchData();
     }, []);
-  
-  
+
+    const loginWithOAuth = async (token) => {
+      const res = await fetch(
+        `${import.meta.env.VITE_BACKEND_URL}/api/auth/callback?code=${encodeURIComponent(token)}`
+      );
+      const data = await res.json();
+
+      if (!res.ok) {
+        throw new Error(data.message || "OAuth login failed");
+      }
+
+      localStorage.setItem("token", data.token);
+      setUser(data.user);
+      return data.user;
+    };
+
     const logout = () => {
       localStorage.removeItem("token");
       setUser(null);
     };
+
     const editUser = async (updatedFields) => {
       try {
         const response = await fetch(
@@ -52,12 +73,12 @@ import React, {
             method: "PUT",
             headers: {
               "Content-Type": "application/json",
-              Authorization: `Bearer ${localStorage.getItem("token")}`,
+              "x-auth-token": localStorage.getItem("token"),
             },
             body: JSON.stringify(updatedFields),
           }
         );
-  
+
         if (response.ok) {
           const updatedUser = await response.json();
           setUser((prevUser) => ({
@@ -81,7 +102,7 @@ import React, {
         throw new Error("An error occurred during user update");
       }
     };
-  
+
     const sendPasswordResetEmail = async (email) => {
       try {
         const response = await fetch(
@@ -94,11 +115,11 @@ import React, {
             body: JSON.stringify({ mail: email }),
           }
         );
-  
+
         if (response.ok) {
           return "Password reset email sent successfully";
         }
-  
+
         const data = await response.json();
         throw new Error(data.message || "Error sending password reset email");
       } catch (error) {
@@ -108,12 +129,13 @@ import React, {
         );
       }
     };
-  
+
     const authContextValue = useMemo(() => {
       return {
         user,
         loading,
         logout,
+        loginWithOAuth,
         editUser,
         sendPasswordResetEmail,
         setUser: (newUser) => {
@@ -121,22 +143,24 @@ import React, {
         },
       };
     }, [user, loading, logout]);
-  
+
     return (
       <AuthContext.Provider value={authContextValue}>
         {children}
       </AuthContext.Provider>
     );
   };
-  
+
   AuthProvider.propTypes = {
     children: PropTypes.node.isRequired,
   };
-  
+
   const useAuth = () => {
     const context = useContext(AuthContext);
     if (!context) {
       throw new Error("useAuth must be used within an AuthProvider");
     }
     return context;
-  };
+  };
+
+  export { AuthProvider, useAuth };