fix: pass UUID approval ID as string, not parseInt (closes #4)

The approval ID was changed from sequential integers to crypto.randomUUID()
strings for security, but the popup still called parseInt() on it, which
converted the UUID to NaN. This caused every approval lookup to fail,
preventing the confirmation popup from displaying pending tx/sign requests.

src/popup/index.js

@@ -189,7 +189,7 @@ async function init() {
     const params = new URLSearchParams(window.location.search);
     const approvalId = params.get("approval");
     if (approvalId) {
-        approval.show(parseInt(approvalId, 10));
+        approval.show(approvalId);
         showView("approve-site");
         return;
     }