fix: reset validation state when navigating to send view

Clear the error/warning text and disable the review button when entering
the send view from home, address detail, or address token views. This
prevents stale validation messages from persisting after leaving and
returning to the send view.

src/popup/views/send.js

@@ -276,4 +276,19 @@ function init(_ctx) {
     });
 }
 
-module.exports = { init, updateSendBalance, renderSendTokenSelect };
+function resetSendValidation() {
+    const errorEl = $("send-to-error");
+    const btn = $("btn-send-review");
+    if (errorEl) errorEl.textContent = "";
+    if (btn) {
+        btn.disabled = true;
+        btn.classList.add("opacity-50");
+    }
+}
+
+module.exports = {
+    init,
+    updateSendBalance,
+    renderSendTokenSelect,
+    resetSendValidation,
+};