Polymer Patch For Servux

fix: resolve item ghosting and implement vanilla conversion for Servux data

• Updated project compatibility for Minecraft 1.21.11.
• Refactored core conversion logic to eliminate item ghosting (desync) issues.
• Implemented a robust NBT filtering system to sanitize modded data sent via Servux.
• Added full support for Polymer and Filament items, ensuring they are correctly mapped to vanilla counterparts for mod-less clients.
• Introduced a caching mechanism (ConcurrentHashMap) to optimize performance during deep NBT scans.
• Fixed an issue where modded IDs were improperly wrapped in Optional strings, causing client-side crashes.