Widget: dispatch bitlogin-offer-pending when the offer screen shows

Hosts that keep the element hidden until needed (the recommended
permanent-mount pattern) listen for this to reveal it; the silent
outcomes (duplicate, unavailable) never fire it, so nothing flashes
for a no-op. Already shipped in the vendored builds consuming this --
the source line lagged the artifact, which this commit corrects.

Co-Authored-By: Claude Fable 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01CMr9Yt8SYmZcfgrg3CV2G1

packages/widget/src/element.ts

@@ -289,6 +289,10 @@ export class BitLoginAuthElement extends HTMLElement {
         label: options.label?.trim() || `${appName} wallet`,
         resolve
       };
+      // Hosts that keep this element hidden until needed (the recommended
+      // permanent-mount pattern) listen for this to reveal it: the silent
+      // outcomes above never fire it, so nothing flashes for a duplicate.
+      this.dispatchEvent(new CustomEvent("bitlogin-offer-pending"));
       this.goto("vault-offer");
     });
   }