feat: MEV toggle, SDK pool queries, token enrichment, indexer lag monitoring (#65 #71 #83 #86)

[charityagbenu12-cmd]

Summary

Implements four features across frontend, SDK, and backend.

Vatix-Protocol#65 [Feat/frontend] MEV Protection Toggle

• hooks/useMevProtection.ts persists toggle in localStorage, resolves correct RPC URL
• components/MevToggle.tsx accessible switch with tooltip and Active badge
• components/SwapSettings.tsx slippage + MEV toggle panel
• components/SwapCard.tsx shows animated protected-submission banner during tx
• Toggle off by default; protected RPC via NEXT_PUBLIC_MEV_PROTECTED_RPC_URL

Vatix-Protocol#71 [Feat/sdk] Pool Query Helpers in @swyft/sdk

• getPool, getPosition, getTick wrapping Soroban RPC
• Fully typed responses, SwyftRpcError, zero any
• Full unit test coverage with mocked RPC
• README quickstart with getPool + swap quote end-to-end

Vatix-Protocol#83 [Feat/backend] Token Metadata Enrichment Service

• Fetches symbol/name/decimals from Soroban RPC and logo from TOKEN_LIST_URL
• GET /tokens returns enriched list
• Token model added to prisma/schema.prisma

Vatix-Protocol#86 [Feat/backend] Indexer Lag Monitoring

• Polls Horizon every 30s, computes lag vs Redis indexer:last_ledger
• WARN on degraded, ERROR + Sentry on critical
• GET /metrics/indexer (INTERNAL_API_KEY protected) and GET /health with indexer status