Real-time chart & order book

This work packages a full real-time market stack for exchange and fintech products: the backend streams normalized OHLC and depth updates over WebSockets while the frontend renders a dense trading terminal—pair header stats, multi-timeframe K-line chart, volume histogram, and a two-sided order book with live bid/ask levels.

Implementation covers indicator overlays (e.g. multiple MAs), cursor-driven OHLC readouts, and layout patterns familiar from professional trading venues: asset sidebar with search and filters, chart mode switches (original vs TradingView-style vs depth), and recent-transaction views next to the book.

The goal is reusable building blocks for teams shipping spot exchange, brokerage, or institutional fintech surfaces: consistent contracts for candle payloads, book snapshots and deltas, and UI states that stay coherent under fast tick updates.