Add WalletConnect: connect from any mobile browser (no dApp browser)

Mobile users in a normal browser hit "no wallet found" because EIP-6963 only
sees injected/extension wallets. WalletConnect fixes it: the connect picker now
offers WalletConnect (auto-selected when no injected wallet is present), which
shows a QR on desktop and opens the wallet app directly on mobile — no in-app
dApp browser, no second login. Lazy-loads the @walletconnect/ethereum-provider
UMD from jsdelivr; the result is a plain EIP-1193 provider so sign/switch/buy are
unchanged. CSP widened for the SDK + WC relay. Project id lives in site config
(public value); gated so nothing changes until it's set.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

public/assets/wallet.js

@@ -52,12 +52,51 @@ window.IAPWallet = (function () {
       card.appendChild(cancel); back.appendChild(card); document.body.appendChild(back);
     });
   }
+  // ── WalletConnect: works in any normal mobile browser (no in-app dApp browser
+  //    needed) and on desktop via QR. Lazy-loaded UMD; the returned object is a
+  //    plain EIP-1193 provider, so everything downstream is unchanged.
+  let wcSdkPromise = null, wcProvider = null;
+  function loadWcSdk() {
+    const ready = () => (window['@walletconnect/ethereum-provider'] || {}).EthereumProvider;
+    if (ready()) return Promise.resolve(ready());
+    if (wcSdkPromise) return wcSdkPromise;
+    wcSdkPromise = new Promise((resolve, reject) => {
+      const s = document.createElement('script');
+      s.src = 'https://cdn.jsdelivr.net/npm/@walletconnect/ethereum-provider@2.21.1/dist/index.umd.js';
+      s.async = true;
+      s.onload = () => { const EP = ready(); EP ? resolve(EP) : reject(new Error('WalletConnect failed to load.')); };
+      s.onerror = () => reject(new Error('Could not load WalletConnect. Check your connection and try again.'));
+      document.head.appendChild(s);
+    });
+    return wcSdkPromise;
+  }
+  async function makeWalletConnect(c) {
+    const projectId = String(c.walletConnectProjectId || '').trim();
+    if (!projectId) throw new Error('WalletConnect is not configured yet.');
+    const EP = await loadWcSdk();
+    const chainId = Number(c.chainId);
+    if (!wcProvider) {
+      wcProvider = await EP.init({
+        projectId, chains: [chainId], optionalChains: [chainId], showQrModal: true,
+        rpcMap: { [chainId]: c.rpc },
+        metadata: { name: c.siteName || 'InstantAdPay', description: c.tagline || 'Advertise and earn, paid on-chain.',
+          url: location.origin, icons: [location.origin + '/logo-icon.png'] }
+      });
+    }
+    if (!wcProvider.session) await wcProvider.connect(); // QR on desktop, opens the wallet app on mobile
+    return wcProvider;
+  }
   async function ensureProvider() {
     if (CHOSEN && CHOSEN.provider) return CHOSEN.provider;
     const list = providerList();
+    let cfg = null;
+    try { cfg = await IAP.getConfig(); } catch (e) {}
+    const wcOn = !!(cfg && String(cfg.walletConnectProjectId || '').trim());
+    if (wcOn) list.push({ info: { name: 'WalletConnect — scan a QR or open your wallet app', __wc: true } });
     if (!list.length) throw new Error('No wallet found. Open this page in your wallet app (Trust, MetaMask, SafePal, Phantom, OKX, TokenPocket) or install a wallet extension.');
-    CHOSEN = list.length === 1 ? list[0] : await pickModal(list);
-    if (!CHOSEN) throw new Error('No wallet selected.');
+    const pick = list.length === 1 ? list[0] : await pickModal(list);
+    if (!pick) throw new Error('No wallet selected.');
+    CHOSEN = (pick.info && pick.info.__wc) ? { info: pick.info, provider: await makeWalletConnect(cfg) } : pick;
     return CHOSEN.provider;
   }
   function eth() {

public/index.html

@@ -439,7 +439,7 @@
 </section>
 
 <script src="/assets/common.js?v=20260908c"></script>
-<script src="/assets/wallet.js?v=20260907q"></script>
+<script src="/assets/wallet.js?v=20260908a"></script>
 <script src="/assets/home.js?v=20260906m"></script>
 <script src="/assets/chat.js?v=20260906m"></script>
 </body>

public/my.html

@@ -690,7 +690,7 @@
   </div>
 </div>
 <script src="/assets/common.js?v=20260908c"></script>
-<script src="/assets/wallet.js?v=20260907q"></script>
+<script src="/assets/wallet.js?v=20260908a"></script>
 <script src="/assets/my.js?v=20260908h"></script>
 <script src="/assets/chat.js?v=20260907l"></script>
 </body>