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).

backend/tests/test_new_strategies.py

@@ -0,0 +1,99 @@
+from __future__ import annotations
+
+from collections.abc import Sequence
+
+from app.engine.strategies.base import StrategyContext
+from app.schemas import Candle
+
+
+def make_candles(closes: Sequence[float]) -> list[Candle]:
+    return [Candle(ts=i, open=c, high=c, low=c, close=c, volume=1.0) for i, c in enumerate(closes)]
+
+
+def context(closes: Sequence[float], position=None) -> StrategyContext:
+    candles = make_candles(closes)
+    return StrategyContext(candles=candles, position=position, equity=1000.0, cash=1000.0)
+
+
+def test_all_strategies_discovered() -> None:
+    from app.engine.strategies import list_strategies
+
+    keys = {cls.key for cls in list_strategies()}
+    assert {
+        "sma_cross",
+        "rsi_reversion",
+        "macd_trend",
+        "bollinger_reversion",
+        "donchian_breakout",
+        "ema_cross",
+        "momentum",
+    } <= keys
+
+
+def test_every_strategy_has_spec_and_params() -> None:
+    from app.engine.strategies import list_strategies, strategy_spec
+
+    for cls in list_strategies():
+        spec = strategy_spec(cls)
+        assert spec.key and spec.name and spec.description
+        # Defaults must round-trip through the constructor and be constructible.
+        instance = cls({})
+        assert instance.key == cls.key
+        # A short synthetic series must never raise for a registered strategy.
+        ctx = context([100, 101, 100, 102, 99, 103, 98, 104, 97, 105])
+        instance.on_candle(ctx)
+
+
+def test_ema_cross_enters_on_cross_up() -> None:
+    from app.engine.strategies import get_strategy
+
+    strategy = get_strategy("ema_cross")({"fast": 2, "slow": 4, "trend_filter": 0, "size": 0.5})
+    # Fast EMA dips below the slow EMA, then crosses back above.
+    ctx = context([10, 10, 10, 10, 10, 10, 10, 10, 7, 9, 12])
+    strategy.on_candle(ctx)
+    intents = ctx.take_intents()
+    assert intents and intents[0].action == "enter_long"
+
+
+def test_momentum_enters_on_positive_roc() -> None:
+    from app.engine.strategies import get_strategy
+
+    strategy = get_strategy("momentum")({"period": 3, "entry_threshold": 0.01, "atr_stop_mult": 0})
+    ctx = context([100, 100, 100, 105])
+    strategy.on_candle(ctx)
+    intents = ctx.take_intents()
+    assert intents and intents[0].action == "enter_long"
+
+
+def test_macd_trend_no_intent_when_flat_short_history() -> None:
+    from app.engine.strategies import get_strategy
+
+    strategy = get_strategy("macd_trend")({})
+    ctx = context([100, 101, 102])
+    strategy.on_candle(ctx)
+    assert ctx.take_intents() == []
+
+
+def test_bollinger_enters_below_lower_band() -> None:
+    from app.engine.strategies import get_strategy
+
+    strategy = get_strategy("bollinger_reversion")(
+        {"period": 5, "num_std": 1.0, "atr_stop_mult": 0}
+    )
+    # Flat then a sharp drop below the lower band.
+    ctx = context([100, 100, 100, 100, 80])
+    strategy.on_candle(ctx)
+    intents = ctx.take_intents()
+    assert intents and intents[0].action == "enter_long"
+
+
+def test_donchian_enters_on_breakout() -> None:
+    from app.engine.strategies import get_strategy
+
+    strategy = get_strategy("donchian_breakout")(
+        {"entry_period": 5, "exit_period": 3, "atr_stop_mult": 0}
+    )
+    ctx = context([100, 100, 100, 100, 100, 110])
+    strategy.on_candle(ctx)
+    intents = ctx.take_intents()
+    assert intents and intents[0].action == "enter_long"