Add home navigation button and improve account page UI

Enhances the account page navigation by adding a "Back to home" button and improving the overall user experience with better visual hierarchy and navigation flow.

Changes:
- Add home navigation button to account page with green icon
- Update logout button styling with red icon for visual emphasis
- Improve settings button label clarity
- Fix settings cancel button to navigate back to account page
- Increase account icon size in page header
- Update translation keys for consistency across EN/HR

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

messages/en.json

@@ -4,8 +4,9 @@
   },
   "account-page": {
     "title": "User account",
-    "settings-button": "User Settings",
-    "logout-button": "Logout"
+    "goto-home-button-label": "Back to home",
+    "goto-settings-button-label": "User Settings",
+    "logout-button-label": "Logout"
   },
   "PageFooter": {
     "app-description": "Helping you to stay on top of your utility bills",

messages/hr.json

@@ -4,8 +4,9 @@
   },
   "account-page": {
     "title": "Korisnički račun",
-    "settings-button": "Korisničke postavke",
-    "logout-button": "Odjava"
+    "goto-home-button-label": "Povratak na početnu",
+    "goto-settings-button-label": "Korisničke postavke",
+    "logout-button-label": "Odjava"
   },
   "PageFooter": {
     "app-description": "Preuzmite kontrolu nad svojim režijama!",