Hide Subscape features (#3697)

Resolves #3673

### What

Let's hide banners and floating link to Subscape for interseason period.

### Testing

- [x] there should be no Subscape link on the wallet page
- [x] there should be no banner mentioning Subscape visible on the
wallet page

Latest build:
[extension-builds-3697](https://github.com/tahowallet/extension/suites/18971874623/artifacts/1109093069)
(as of Tue, 12 Dec 2023 12:50:33 GMT).

.env.defaults

@@ -30,6 +30,7 @@ SUPPORT_ARBITRUM_NOVA=false
 SUPPORT_SWAP_QUOTE_REFRESH=false
 SUPPORT_ACHIEVEMENTS_BANNER=false
 SUPPORT_NFT_SEND=false
+HIDE_ISLAND_UI=true
 SUPPORT_THE_ISLAND=true
 SUPPORT_THE_ISLAND_ON_TENDERLY=false
 USE_MAINNET_FORK=false

background/features.ts

@@ -23,6 +23,7 @@ export const RuntimeFlag = {
   SUPPORT_SWAP_QUOTE_REFRESH: process.env.SUPPORT_SWAP_QUOTE_REFRESH === "true",
   SUPPORT_CUSTOM_NETWORKS: process.env.SUPPORT_CUSTOM_NETWORKS === "true",
   SUPPORT_CUSTOM_RPCS: process.env.SUPPORT_CUSTOM_RPCS === "true",
+  HIDE_ISLAND_UI: process.env.HIDE_ISLAND_UI === "true",
   SUPPORT_THE_ISLAND: process.env.SUPPORT_THE_ISLAND === "true",
   SUPPORT_THE_ISLAND_ON_TENDERLY:
     process.env.SUPPORT_THE_ISLAND_ON_TENDERLY === "true",

ui/pages/Wallet.tsx

@@ -102,7 +102,7 @@ export default function Wallet(): ReactElement {
   return (
     <>
       <div className="page_content">
-        <WalletSubspaceLink />
+        {!isEnabled(FeatureFlags.HIDE_ISLAND_UI) && <WalletSubspaceLink />}
         <WalletAnalyticsNotificationBanner />
         <div className="section">
           <WalletAccountBalanceControl
@@ -116,7 +116,7 @@ export default function Wallet(): ReactElement {
         {!isEnabled(FeatureFlags.HIDE_TOKEN_FEATURES) && (
           <OnboardingOpenClaimFlowBanner />
         )}
-        <PortalBanner />
+        {!isEnabled(FeatureFlags.HIDE_ISLAND_UI) && <PortalBanner />}
         <div className="section">
           <SharedPanelSwitcher
             setPanelNumber={setPanelNumber}