Add localized search functionality for contacts (#244)

- Introduced new localization keys for searching contacts, users, favorites, repeaters, and room servers in multiple languages.
- Updated localization files for Italian, Bulgarian, German, English, Spanish, French, Dutch, Polish, Portuguese, Russian, Slovak, Slovenian, Swedish, Ukrainian, and Chinese.
- Enhanced the contacts screen to dynamically display search hints based on the selected contact type filter.
- Modified the map screen to utilize the new search functionality for contacts without a number.

lib/l10n/app_nl.arb

@@ -1753,5 +1753,51 @@
   },
   "listFilter_removeFromFavorites": "Verwijderen uit favorieten",
   "listFilter_favorites": "Favorieten",
-  "listFilter_addToFavorites": "Toevoegen aan favorieten"
+  "listFilter_addToFavorites": "Toevoegen aan favorieten",
+  "@contacts_searchFavorites": {
+    "placeholders": {
+      "number": {
+        "type": "int"
+      },
+      "str": {
+        "type": "String"
+      }
+    }
+  },
+  "@contacts_searchUsers": {
+    "placeholders": {
+      "number": {
+        "type": "int"
+      },
+      "str": {
+        "type": "String"
+      }
+    }
+  },
+  "@contacts_searchRepeaters": {
+    "placeholders": {
+      "number": {
+        "type": "int"
+      },
+      "str": {
+        "type": "String"
+      }
+    }
+  },
+  "@contacts_searchRoomServers": {
+    "placeholders": {
+      "number": {
+        "type": "int"
+      },
+      "str": {
+        "type": "String"
+      }
+    }
+  },
+  "contacts_unread": "Ongelezen",
+  "contacts_searchRepeaters": "Zoek {number}{str} Repeaters...",
+  "contacts_searchContactsNoNumber": "Zoek contacten...",
+  "contacts_searchUsers": "Zoek {number}{str} gebruikers...",
+  "contacts_searchFavorites": "Zoek {number}{str} favorieten...",
+  "contacts_searchRoomServers": "Zoek {number}{str} Room servers..."
 }