Switch from SuperTokens to NextAuth.js

BREAKING CHANGE: Replace SuperTokens with NextAuth.js

Why:
- SuperTokens had persistent Traefik routing issues
- SSL certificate not issuing correctly
- Complex infrastructure (separate container)
- NextAuth runs in Next.js app (simpler, no separate service)

Changes:
- Install next-auth, @auth/prisma-adapter, prisma
- Create NextAuth API route: app/api/auth/[...nextauth]/route.ts
- Add Prisma schema for NextAuth tables (users, sessions, accounts)
- Update auth page to use NextAuth signIn()
- Remove all SuperTokens code and dependencies
- Keep same Google OAuth (just simpler integration)

Benefits:
- No separate auth service needed
- No Traefik routing issues
- Sessions stored in Montreal PostgreSQL
- Simpler configuration
- Battle-tested, widely used

All authentication data stays in Montreal!

Co-authored-by: Cursor <cursoragent@cursor.com>

lib/auth/authOptions.ts

@@ -0,0 +1,33 @@
+import { NextAuthOptions } from "next-auth";
+import GoogleProvider from "next-auth/providers/google";
+import { PrismaAdapter } from "@auth/prisma-adapter";
+import { PrismaClient } from "@prisma/client";
+
+const prisma = new PrismaClient();
+
+export const authOptions: NextAuthOptions = {
+  adapter: PrismaAdapter(prisma),
+  providers: [
+    GoogleProvider({
+      clientId: process.env.GOOGLE_CLIENT_ID || "",
+      clientSecret: process.env.GOOGLE_CLIENT_SECRET || "",
+    }),
+  ],
+  pages: {
+    signIn: "/auth",
+    error: "/auth",
+  },
+  callbacks: {
+    async session({ session, user }) {
+      if (session.user) {
+        session.user.id = user.id;
+      }
+      return session;
+    },
+  },
+  session: {
+    strategy: "database",
+    maxAge: 30 * 24 * 60 * 60, // 30 days
+  },
+  secret: process.env.NEXTAUTH_SECRET,
+};

lib/supertokens/backendConfig.ts

@@ -1,55 +0,0 @@
-import ThirdPartyNode from "supertokens-node/recipe/thirdparty";
-import EmailPasswordNode from "supertokens-node/recipe/emailpassword";
-import SessionNode from "supertokens-node/recipe/session";
-import { TypeInput } from "supertokens-node/types";
-import { AppInfoUserInput } from "supertokens-node/types";
-
-export const backendConfig = (): TypeInput => {
-  const appUrl = process.env.NEXT_PUBLIC_APP_URL || "https://vibnai.com";
-  
-  const appInfo: AppInfoUserInput = {
-    appName: "Vib'n",
-    apiDomain: appUrl,
-    websiteDomain: appUrl,
-    apiBasePath: "/api/auth",
-    websiteBasePath: "/auth",
-  };
-
-  return {
-    framework: "custom",
-    supertokens: {
-      connectionURI: process.env.SUPERTOKENS_CONNECTION_URI || "http://j04ckwg0k040o08gc04gs80o:3567",
-      apiKey: process.env.SUPERTOKENS_API_KEY || "",
-    },
-    appInfo,
-    recipeList: [
-      ThirdPartyNode.init({
-        signInAndUpFeature: {
-          providers: [
-            {
-              config: {
-                thirdPartyId: "google",
-                clients: [{
-                  clientId: process.env.GOOGLE_CLIENT_ID || "",
-                  clientSecret: process.env.GOOGLE_CLIENT_SECRET || "",
-                }],
-              },
-            },
-            {
-              config: {
-                thirdPartyId: "github",
-                clients: [{
-                  clientId: process.env.GITHUB_CLIENT_ID || "",
-                  clientSecret: process.env.GITHUB_CLIENT_SECRET || "",
-                }],
-              },
-            },
-          ],
-        },
-      }),
-      EmailPasswordNode.init(),
-      SessionNode.init(),
-    ],
-    isInServerlessEnv: true,
-  };
-};

lib/supertokens/frontendConfig.ts

@@ -1,29 +0,0 @@
-import ThirdParty, { Google, Github } from "supertokens-auth-react/recipe/thirdparty";
-import EmailPassword from "supertokens-auth-react/recipe/emailpassword";
-import Session from "supertokens-auth-react/recipe/session";
-
-export const frontendConfig = () => {
-  const appUrl = process.env.NEXT_PUBLIC_APP_URL || "https://app.vibnai.com";
-  
-  return {
-    appInfo: {
-      appName: "Vib'n",
-      apiDomain: appUrl,
-      websiteDomain: appUrl,
-      apiBasePath: "/api/auth",
-      websiteBasePath: "/auth",
-    },
-    recipeList: [
-      ThirdParty.init({
-        signInAndUpFeature: {
-          providers: [
-            Google.init(),
-            Github.init(),
-          ],
-        },
-      }),
-      EmailPassword.init(),
-      Session.init(),
-    ],
-  };
-};