feat: shop buy, forum replies, tickets, messages, sessions, and UX hardening

Complete remaining product gaps: credit-based shop purchases, guild thread replies, help ticket detail/reply/close, offline message compose, sign-out-everywhere via JWT version, ads delete confirm, soft-fail feedback, rate limits, loading states, and single auth() in site layout.

Co-authored-by: Cursor <[email protected]>

src/app/(site)/draw-badge/page.tsx

@@ -26,12 +26,14 @@ const BOUGHT_NOTE = (code: string) =>
 const ERROR_NOTE: Record<string, string> = {
 	invalid: "That badge is no longer available.",
 	credits: "You don't have enough credits to buy this badge.",
+	ratelimit: "You're purchasing too fast. Please wait a moment and try again.",
 	fail: "Something went wrong. Please try again.",
 };
 
 function getErrorNote(error: string): string {
 	if (error === "invalid") return ERROR_NOTE.invalid;
 	if (error === "credits") return ERROR_NOTE.credits;
+	if (error === "ratelimit") return ERROR_NOTE.ratelimit;
 	return ERROR_NOTE.fail;
 }