Bitcoin favicon, more strategies, default timeframe 5m

- Add an SVG Bitcoin favicon and link it in index.html.
- New indicators: macd() and roc().
- Five new strategies: macd_trend, bollinger_reversion, donchian_breakout,
  ema_cross, momentum (plus the existing sma_cross, rsi_reversion).
- Default TIMEFRAME is now 5m (config, .env.example, compose, workflow, UI).

docker-compose.local.yml

@@ -12,7 +12,7 @@ services:
       - MODE=${MODE:-paper}
       - EXCHANGE=${EXCHANGE:-binance}
       - SYMBOL=${SYMBOL:-BTC/USDT}
-      - TIMEFRAME=${TIMEFRAME:-1m}
+      - TIMEFRAME=${TIMEFRAME:-5m}
       - POLL_INTERVAL=${POLL_INTERVAL:-5}
       - STARTING_BALANCE=${STARTING_BALANCE:-10000}
       - FEE_BPS=${FEE_BPS:-10}