feat(market): add Minha Intenções tab with panel, hook, and badge

- Introduced "Minhas Intenções" tab visible only to logged-in users.
- Integrated MyPurchaseIntentionsPanel and useMyPurchaseIntentions hook.
- Added tab badge showing count of pending intentions.
- Extended session API to include user’s main character for downstream features.

lib/utils.ts

@@ -4,3 +4,22 @@ import { twMerge } from "tailwind-merge"
 export function cn(...inputs: ClassValue[]) {
   return twMerge(clsx(inputs))
 }
+
+/**
+ * Formata uma data para string relativa (ex: "há 2 horas")
+ */
+export function formatTimeAgo(date: Date | string): string {
+  const dateObj = typeof date === "string" ? new Date(date) : date;
+  const seconds = Math.floor((new Date().getTime() - dateObj.getTime()) / 1000);
+  if (seconds < 60) return "há alguns segundos";
+  const minutes = Math.floor(seconds / 60);
+  if (minutes < 60) return `há ${minutes} ${minutes === 1 ? "minuto" : "minutos"}`;
+  const hours = Math.floor(minutes / 60);
+  if (hours < 24) return `há ${hours} ${hours === 1 ? "hora" : "horas"}`;
+  const days = Math.floor(hours / 24);
+  if (days < 30) return `há ${days} ${days === 1 ? "dia" : "dias"}`;
+  const months = Math.floor(days / 30);
+  if (months < 12) return `há ${months} ${months === 1 ? "mês" : "meses"}`;
+  const years = Math.floor(months / 12);
+  return `há ${years} ${years === 1 ? "ano" : "anos"}`;
+}