feat(update-modal): display last 5 release notes instead of single

- Modified backend to fetch last 5 releases from GitHub API
- Updated frontend to iterate through and display multiple releases
- Added latest badge and publish date styling
- Added update.latestBadge translation key to all locales
- Maintains backward compatibility for single changelog display

locales/he.json

@@ -1214,6 +1214,7 @@
         "checkingUpdates": "בודק עדכונים...",
         "checkingMessage": "אנא המתן בזמן שאנו בודקים את הגרסה האחרונה.",
         "showNotifications": "הצג התראות עדכון",
+        "latestBadge": "עדכן",
         "updateProgress": {
             "preparing": "מכין עדכון...",
             "installing": "מתקין עדכון...",