fix(critique): 2 régressions introduites par les fixes précédents

Bug #1 — Memory Echo cassé (runtime crash):
- lib/ai/services/memory-echo.service.ts: lignes adjustedThreshold restaurées
- Cause: sed console.log avait supprimé les lignes de définition
- Effet: findConnections() crashait (ReferenceError)

Bug #2 — Auth mobile totalement cassée (sécurité):
- 14 routes app/api/mobile/*/: getMobileUserId(req) → await getMobileUserId(req)
- Cause: verifyMobileToken devenu async mais callers non mis à jour
- Effet: auth bypassée (Promise truthy au lieu de string)

i18n:
- searchModal.* + insightsView.* propagés dans 13 locales (EN fallback)

memento-note/locales/fa.json

@@ -3046,5 +3046,27 @@
     "listView": "List",
     "graphAriaLabel": "Semantic network: {clusters} clusters, {notes} notes, {bridges} bridge notes. Switch to List view for accessible navigation.",
     "listAriaLabel": "Accessible cluster list with notes and bridge connections"
+  },
+  "searchModal": {
+    "search_ariaLabel": "Search",
+    "search_placeholder": "Search across all your notes…",
+    "search_caseSensitive": "Case sensitive",
+    "search_regexMode": "Regex mode",
+    "search_trashIncluded": "Trash included",
+    "search_openInEditor": "Open in editor",
+    "search_title": "Memento Search",
+    "search_favorites": "Favorites:",
+    "search_searching": "Searching…",
+    "search_noResults": "No results",
+    "search_typeToSearch": "Type to search",
+    "search_aiAnalysis": "Analyzing…",
+    "search_aiResponse": "AI Response",
+    "search_resultsSummary": "Results summary…",
+    "search_documentPreview": "Document preview",
+    "search_noMatch": "No note matches.",
+    "search_typeForResults": "Type to get instant results.",
+    "search_hintNavigate": "navigate",
+    "search_hintOpen": "open",
+    "search_hintClose": "close"
   }
 }