Add Next.js client app with Prisma and auth

Introduce a new 'client' Next.js app scaffold: configuration files (next.config.ts, eslint.config.mjs, postcss, tsconfig), Prisma config and schema, app routes including NextAuth API and server actions, session/provider utilities, proxy, public assets, README and .gitignore. Also add IDE project files under .idea and a root README to initialize the repository structure for development.

client/src/app/api/auth/[...nextauth]/serverActions.ts

@@ -0,0 +1,28 @@
+//auth functions again teh database go here and get then gen imported to the route file to be used
+"use server";
+
+import { prisma } from "@/lib/prisma";
+
+type UpsertGoogleUserInput = {
+	email: string;
+	name?: string | null;
+};
+
+export const createUserOnFirstGoogleLogin = async ({
+	email,
+	name,
+}: UpsertGoogleUserInput) => {
+	const existingUser = await prisma.user.findUnique({
+		where: { email },
+		select: { id: true },
+	});
+
+	if (!existingUser) {
+		await prisma.user.create({
+			data: {
+				email,
+				name: name ?? null,
+			},
+		});
+	}
+};