fix(store): specific rate-limit message on tier change + use shared dialogs for subscription flows (#4622)

## Summary

- The change-tier API allows one tier change per minute per player
(`playerRateLimit` on `/subscriptions/@me/change-tier`). The client
previously lumped the 429 in with every other failure and showed
"Couldn't update your subscription. Please try again." — retrying
immediately just fails again. A 429 now gets its own message: *"You just
changed tiers. Please wait a minute before changing again."*
- Replaced all native `alert()` / `window.confirm()` calls in the
subscription flows with the shared `showInGameAlert` /
`showInGameConfirm` helpers (styled `<confirm-dialog>`, consistent with
the rest of the store, and safe on CrazyGames):
- Tier change: already-subscribed notice, upgrade/downgrade confirmation
(warning variant with "Change Tier" heading),
rate-limited/failure/success notices
  - Dollar checkout failures (first-time subscribe path)
- Subscription panel: cancel confirmation (danger variant), cancel
failure/success, portal-open failure

The currency-purchase alerts in Cosmetics.ts (`login_required`,
`purchase_failed`, `purchase_success`) are untouched — subscriptions
can't reach that path.

## Test plan

- [x] Typecheck, ESLint, Prettier
- [ ] Manual: change tier twice within a minute against the real API and
confirm the rate-limit dialog appears

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

src/client/Api.ts

@@ -410,7 +410,7 @@ export async function cancelSubscription(): Promise<boolean> {
 
 export async function changeSubscriptionTier(
   tierName: string,
-): Promise<boolean> {
+): Promise<boolean | "rate_limited"> {
   try {
     const response = await fetch(
       `${getApiBase()}/subscriptions/@me/change-tier`,
@@ -427,6 +427,10 @@ export async function changeSubscriptionTier(
       await logOut();
       return false;
     }
+    // The API allows one tier change per minute per player.
+    if (response.status === 429) {
+      return "rate_limited";
+    }
     if (!response.ok) {
       console.error(
         "changeSubscriptionTier: request failed",

src/client/Cosmetics.ts

@@ -29,6 +29,7 @@ import {
   invalidateUserMe,
   purchaseWithCurrency,
 } from "./Api";
+import { showInGameAlert, showInGameConfirm } from "./InGameModal";
 import { translateText } from "./Utils";
 
 export const TEMP_FLARE_OFFSET = 1 * 60 * 1000; // 1 minute
@@ -92,7 +93,7 @@ export async function purchaseCosmetic(
 
     if (currentSub) {
       if (currentSub.tier === sub.name) {
-        alert(translateText("store.already_subscribed"));
+        await showInGameAlert(translateText("store.already_subscribed"));
         return;
       }
 
@@ -108,17 +109,27 @@ export async function purchaseCosmetic(
       const confirmKey = isUpgrade
         ? "store.confirm_upgrade"
         : "store.confirm_downgrade";
-      const confirmed = window.confirm(
+      const confirmed = await showInGameConfirm(
         translateText(confirmKey, { tier: targetName }),
+        {
+          heading: translateText("account_modal.change_tier"),
+          variant: "warning",
+        },
       );
       if (!confirmed) return;
 
-      const ok = await changeSubscriptionTier(sub.name);
-      if (!ok) {
-        alert(translateText("store.change_tier_failed"));
+      const result = await changeSubscriptionTier(sub.name);
+      if (result === "rate_limited") {
+        await showInGameAlert(translateText("store.change_tier_rate_limited"));
         return;
       }
-      alert(translateText("store.change_tier_success", { tier: targetName }));
+      if (!result) {
+        await showInGameAlert(translateText("store.change_tier_failed"));
+        return;
+      }
+      await showInGameAlert(
+        translateText("store.change_tier_success", { tier: targetName }),
+      );
       window.location.reload();
       return;
     }
@@ -126,7 +137,7 @@ export async function purchaseCosmetic(
 
   if (method === "dollar") {
     if (!c.product) {
-      alert(translateText("store.checkout_failed"));
+      await showInGameAlert(translateText("store.checkout_failed"));
       return;
     }
     const url = await createCheckoutSession(
@@ -134,7 +145,7 @@ export async function purchaseCosmetic(
       colorPaletteName,
     );
     if (url === false) {
-      alert(translateText("store.checkout_failed"));
+      await showInGameAlert(translateText("store.checkout_failed"));
       return;
     }
     window.location.href = url;

src/client/components/SubscriptionPanel.ts

@@ -8,6 +8,7 @@ import {
   openSubscriptionPortal,
 } from "../Api";
 import { translateCosmetic } from "../Cosmetics";
+import { showInGameAlert, showInGameConfirm } from "../InGameModal";
 import { translateText } from "../Utils";
 import "./baseComponents/Button";
 import "./CapIcon";
@@ -28,7 +29,9 @@ export class SubscriptionPanel extends LitElement {
   private handleManage = async (): Promise<void> => {
     const url = await openSubscriptionPortal();
     if (url === false) {
-      alert(translateText("account_modal.subscription_portal_failed"));
+      await showInGameAlert(
+        translateText("account_modal.subscription_portal_failed"),
+      );
       return;
     }
     window.open(url, "_blank", "noopener,noreferrer");
@@ -39,16 +42,21 @@ export class SubscriptionPanel extends LitElement {
   };
 
   private handleCancel = async (): Promise<void> => {
-    const confirmed = window.confirm(
+    const confirmed = await showInGameConfirm(
       translateText("account_modal.cancel_subscription_confirm"),
+      { heading: translateText("account_modal.cancel_subscription") },
     );
     if (!confirmed) return;
     const ok = await cancelSubscription();
     if (!ok) {
-      alert(translateText("account_modal.cancel_subscription_failed"));
+      await showInGameAlert(
+        translateText("account_modal.cancel_subscription_failed"),
+      );
       return;
     }
-    alert(translateText("account_modal.cancel_subscription_success"));
+    await showInGameAlert(
+      translateText("account_modal.cancel_subscription_success"),
+    );
     invalidateUserMe();
     window.location.reload();
   };