Improve Features page ordering and mobile UI consistency

- Fix module ordering with local state tracking for immediate UI updates
- Add tab centering when selected (scroll to center)
- Use finally block in handleApplyOrder to ensure state reset
- Add cancelOrder translation key
- Increase order card min-width for better readability
- Normalize mobile top bar height with min-height constraint
- Add display:flex to mobile title sections for proper layout

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/src/locales/en.json

@@ -66,6 +66,7 @@
     "orderSection": "Sidebar Order",
     "orderDesc": "Drag to reorder features in the sidebar",
     "applyOrder": "Apply",
+    "cancelOrder": "Cancel",
     "visibility": "Visibility",
     "topSection": "Main Section",
     "bottomSection": "Bottom Section",