feat(frontend): Add billing page toggle (#9877)

### Changes 🏗️

Provide a system toggle for disabling the billing page:
NEXT_PUBLIC_SHOW_BILLING_PAGE

### Checklist 📋

#### For code changes:
- [x] I have clearly listed my changes in the PR description
- [x] I have made a test plan
- [x] I have tested my changes according to the test plan:
  - [x] Toggle `NEXT_PUBLIC_SHOW_BILLING_PAGE` value.

Author: majdyz

autogpt_platform/frontend/.env.example

@@ -24,3 +24,4 @@ GA_MEASUREMENT_ID=G-FH2XK2W4GN
 
 # When running locally, set NEXT_PUBLIC_BEHAVE_AS=CLOUD to use the a locally hosted marketplace (as is typical in development, and the cloud deployment), otherwise set it to LOCAL to have the marketplace open in a new tab
 NEXT_PUBLIC_BEHAVE_AS=LOCAL
+NEXT_PUBLIC_SHOW_BILLING_PAGE=false

autogpt_platform/frontend/src/app/(platform)/profile/(user)/layout.tsx

@@ -18,11 +18,15 @@ export default function Layout({ children }: { children: React.ReactNode }) {
           href: "/profile/dashboard",
           icon: <IconDashboardLayout className="h-6 w-6" />,
         },
-        {
-          text: "Billing",
-          href: "/profile/credits",
-          icon: <IconCoin className="h-6 w-6" />,
-        },
+        ...(process.env.NEXT_PUBLIC_SHOW_BILLING_PAGE === "true"
+          ? [
+              {
+                text: "Billing",
+                href: "/profile/credits",
+                icon: <IconCoin className="h-6 w-6" />,
+              },
+            ]
+          : []),
         {
           text: "Integrations",
           href: "/profile/integrations",

autogpt_platform/frontend/src/components/agptui/Wallet.tsx

@@ -104,7 +104,9 @@ export default function Wallet() {
         </div>
         <ScrollArea className="max-h-[85vh] overflow-y-auto">
           {/* Top ups */}
-          <WalletRefill />
+          {process.env.NEXT_PUBLIC_SHOW_BILLING_PAGE === "true" && (
+            <WalletRefill />
+          )}
           {/* Tasks */}
           <p className="mx-1 mt-4 font-sans text-xs font-medium text-violet-700">
             Onboarding tasks