* fix(frontend): replace innerHTML with DOM API to prevent XSS
Replace all non-clearing .innerHTML assignments in app.js with safe DOM
construction using makeElement() and replaceChildren().
* fix frontend DOM rendering regressions
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Co-authored-by: Fengqing Liu <fq_aaron@hotmail.com>
- Implemented 'Benefit Type' filtering (Item, Badge, etc.) in backend and settings UI.
- Redesigned 'Wanted Drops Queue' as a card-based, masonry layout.
- Added 'Game Groups' to Wanted Queue for better organization.
- Added variable height support for Inventory cards.
- Added proxy support and verification logic (from previous steps).
- Added unit tests for new filters and UI logic.