Add trading_account.capital_usdt. Position sizing will use
min(capital, account equity); starting requires the capital to be set.
The trading page shows and edits it.
Add trading_symbols, trading_analyses, trading_orders and trading_events.
The new trader service publishes account, position and open-order
snapshots of the Binance demo account to Redis every 3s. The /trading
page shows engine status, start/stop, balances, positions, the symbol
list with angle selection, open orders and the event timeline.
eezd