implementing chat archiving (does not work yet)

src/i18n/en.json

@@ -1,5 +1,5 @@
 {
-  "contacts_not_found": "You have no chats<br />¯∖_(ツ)_/¯",
+  "archived_contacts": "Archived contacts ({count})",
   "full_name_prompt": "Full name, e.g. John Doe",
   "email_prompt": "Email, e.g. jdoe@example.com",
   "button_sign_up": "Sign up",
@@ -63,6 +63,7 @@
   "sidepanel_title_newtpk": "Start New Chat",
   "sidepanel_title_cred": "Confirm Credentials",
   "sidepanel_title_reset": "Reset Password",
+  "sidepanel_title_archive": "Archived",
   "update_available": "Update available. <a href=\"\">Reload</a>.",
   "reconnect_countdown": "Disconnected. Reconnecting in {seconds}s…",
   "reconnect_now": "Try now",