XRPL Gaming MongoDB Adapter

MongoDB storage adapter for the Kinesis XRPL DynamicNFT Gaming SDK (v0.2.0). Persists NFT records and ownership history to a single auto-indexed MongoDB collection using NFTokenID as document _id for O(1) reads. Requires peer dependency xrpl-gaming-core ^0.2.0. Self-hosted adapter; managed tier planned. Key differentiator: designed specifically for XRPL gaming with automatic indexes on playerId, ownerAddress, and collection. Ships TypeScript types. Release cadence: early-stage, minor version bumps expected.