fix(duvs): polyfill Promise.try after zone.js patches global Promise

[Raina451]

Issue

On deployed coded apps using the DU validation station widget, the document viewer (PDF/image) fails to render. Fields display correctly but the entire PDF viewer panel is missing. The browser console shows:

TypeError: Promise.try is not a function

This only happens in production builds — local dev works fine.

Root cause

• zone.js (bundled with @uipath/du-validation-station-wc) replaces the global Promise with ZoneAwarePromise, which lacks Promise.try()
• The WC's PDF viewer calls Promise.try() at runtime, causing the TypeError
• In dev mode this doesn't surface because Vite excludes the WC from pre-bundling, so zone.js patches happen in a separate module scope
• In production, everything is bundled together — zone.js patches Promise before the WC code runs

Fix

Inline a Promise.try polyfill in loadValidationStationWc.ts, after the zone.js polyfills import (which patches Promise) but before the WC component renders (which calls Promise.try). ES imports are hoisted, so the polyfill runs after all imports evaluate — this is early enough since Promise.try is only called at render time, not during module initialization.

Remove the polyfill when the WC ships a zone.js version that includes Promise.try.

[github-actions]

📊 Coverage Report

Package	Line Coverage
datatable	88.29%
multi-file-upload	87.27%
conversational-agent-chat	89.09%
validation-station	95.09%