tray: move session-expiry row under profile email, hide separator when daemon unavailable

- Relocate the session-expiry row from below the status item to below the
  profile email so active profile, email, and session deadline form one block.
- Rename the label to "Expires in {remaining}" (en/hu/de).
- Capture the Connect/Disconnect separator via lastMenuItem and hide it when
  both action rows are hidden (daemon unavailable), avoiding two adjacent
  separators with nothing between them.

client/ui/frontend/src/i18n/locales/de/common.json

@@ -3,7 +3,7 @@
     "tray.status.disconnected": "Getrennt",
     "tray.status.daemonUnavailable": "Nicht aktiv",
     "tray.status.error": "Fehler",
-    "tray.session.expiresIn": "Sitzung: {remaining}",
+    "tray.session.expiresIn": "Läuft ab in {remaining}",
 
     "tray.menu.open": "NetBird öffnen",
     "tray.menu.connect": "Verbinden",

client/ui/frontend/src/i18n/locales/en/common.json

@@ -3,7 +3,7 @@
     "tray.status.disconnected": "Disconnected",
     "tray.status.daemonUnavailable": "Not running",
     "tray.status.error": "Error",
-    "tray.session.expiresIn": "Session: {remaining}",
+    "tray.session.expiresIn": "Expires in {remaining}",
 
     "tray.menu.open": "Open NetBird",
     "tray.menu.connect": "Connect",

client/ui/frontend/src/i18n/locales/hu/common.json

@@ -3,7 +3,7 @@
     "tray.status.disconnected": "Lekapcsolva",
     "tray.status.daemonUnavailable": "Nem fut",
     "tray.status.error": "Hiba",
-    "tray.session.expiresIn": "Munkamenet: {remaining}",
+    "tray.session.expiresIn": "Lejár {remaining} múlva",
 
     "tray.menu.open": "NetBird megnyitása",
     "tray.menu.connect": "Csatlakozás",