feat: add backtester and enable ranging-regime filter

fix: calculate active trade P&L and R:R immediately on history loading

Remove unprofitable 15m timeframe symbols (ETHUSDT & EURUSD) from the entire application

Add Reset Account button to UI and wire up API interactions

fix: implement weekend Day-of-Week stats, client cooldown state sync, and client transition scanning

Enable Grade B setups (Score >= 4) in autopilot/client scanners and update Telegram and active trade card UI to display Grade badges

Completely remove and clean up Twelve Data integration from the codebase

feat: implement spot gold offset engine and telegram notification loops with smart SL post-mortems

feat: implement Twelve Data provider integration with secure Express API proxy, automated server-side caching, and key-activated OANDA spot gold/forex upgrade

fix: remove redundant and corrupting chart update inside handleTick to prevent double-candle forming discrepancy

feat: migrate to full-stack cloud autopilot terminal with mongodb atlas