feat(frontend): Server Actions for thought, social, and profile mutations

thoughts-frontend/app/actions/profile.ts

@@ -0,0 +1,23 @@
+"use server";
+
+import { revalidateTag } from "next/cache";
+import { cookies } from "next/headers";
+import { updateProfile as apiUpdateProfile, UpdateProfileSchema } from "@/lib/api";
+import { z } from "zod";
+
+async function getToken(): Promise<string> {
+  const token = (await cookies()).get("auth_token")?.value;
+  if (!token) throw new Error("Not authenticated");
+  return token;
+}
+
+export async function updateProfile(
+  username: string,
+  data: z.infer<typeof UpdateProfileSchema>
+) {
+  const token = await getToken();
+  const updated = await apiUpdateProfile(data, token);
+  revalidateTag(`profile:${username}`);
+  revalidateTag("me");
+  return updated;
+}