Replace hardcoded French strings with i18n calls

Initialize i18n before auth so t() works when rendering
auth-dependent UI, and build the command palette lazily so
translations are loaded first. Bump service worker cache version.

frontend/js/search.js

@@ -847,7 +847,7 @@ export function renderSearchResults(data, query, tagFilter) {
   const header = buildSearchResultsHeader(data, query, tagFilter);
   area.appendChild(header);
   if (data.results.length === 0) {
-    area.appendChild(el("p", { style: "color:var(--text-muted);margin-top:20px" }, [document.createTextNode("Aucun résultat trouvé.")]));
+    area.appendChild(el("p", { style: "color:var(--text-muted);margin-top:20px" }, [document.createTextNode(t("search.no_results"))]));
     return;
   }
   const container = el("div", { class: "search-results" });
@@ -965,7 +965,7 @@ export function renderAdvancedSearchResults(data, query, tagFilter) {
   header.appendChild(sortDiv);
 
   // Save search button
-  const saveBtn = el("button", { class: "search-save-btn", type: "button", title: "Sauvegarder cette recherche" });
+  const saveBtn = el("button", { class: "search-save-btn", type: "button", title: t("search.save_search") });
   saveBtn.innerHTML = '<i data-lucide="bookmark-plus" style="width:14px;height:14px"></i> Sauver';
   saveBtn.addEventListener("click", async () => {
     const inclEl = document.getElementById("search-include-input");
@@ -1063,7 +1063,7 @@ export function renderAdvancedSearchResults(data, query, tagFilter) {
 
   // Empty state
   if (data.results.length === 0) {
-    area.appendChild(el("p", { style: "color:var(--text-muted);margin-top:20px" }, [document.createTextNode("Aucun résultat trouvé.")]));
+    area.appendChild(el("p", { style: "color:var(--text-muted);margin-top:20px" }, [document.createTextNode(t("search.no_results"))]));
     return;
   }