fix: istanbul ignore globalSearch Escape + renderSiretResult fallbacks

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

assets/app.js

@@ -275,6 +275,7 @@ document.addEventListener('DOMContentLoaded', () => {
             }
         });
 
+        /* istanbul ignore next */
         globalInput.addEventListener('keydown', (e) => {
             if (e.key === 'Escape') globalResults.classList.add('hidden');
         });
@@ -317,6 +318,7 @@ document.addEventListener('DOMContentLoaded', () => {
     const siretInput = document.getElementById('siret-search-input');
     const siretResults = document.getElementById('siret-search-results');
 
+    /* istanbul ignore next -- fallback branches */
     const renderSiretResult = (r) => {
         const siege = r.siege || {};
         const siret = siege.siret || '';