feat(family-09): add 7 trailing stops (HiLo, Volty, Yo-Yo, Donchian, Pct, Step, Renko) (#46)

* feat(family-09): add 7 trailing stops (HiLo, Volty, Yo-Yo, Donchian, Pct, Step, Renko)

Rounds out the Trailing Stops family from 5 to 12 indicators:

- HiLoActivator (Crabel): SMA-of-high/SMA-of-low trail with a one-bar
  lag; emits the opposite-side SMA as the trailing stop.
- VoltyStop (Cynthia Kase): ATR trail anchored on the extreme close
  since the trade was opened — tighter than AtrTrailingStop on
  pullbacks.
- YoyoExit: long-only ATR trail with an explicit re-entry trigger at
  trail + multiplier*ATR; exposes an in_trade flag.
- DonchianStop (Turtle): lowest low / highest high over the window;
  multi-output {stop_long, stop_short}.
- PercentageTrailingStop: fixed-percent trail that scales across
  instruments without per-asset tuning.
- StepTrailingStop: snaps to a step_size-aligned grid; mirrors
  discretionary stop-by-hand workflow.
- RenkoTrailingStop: block-anchored trail; only moves on full-block
  advances, ignores intra-block noise.

All seven are wired into wickra-core, the Python / Node / WASM
bindings, the indicator_update + indicator_update_candle fuzz targets,
the wickra bench harness, and the Python + Node test suites. README
counter bumps from 71 to 78; CHANGELOG entry under [Unreleased].

* fix(family-09): satisfy pedantic clippy lints

- hilo_activator: rewrite match-Some/None as if-let-else (single_match_else),
  add backticks around the HiLo identifier in module/struct doc (doc_markdown).
- percentage / step / renko trailing stop tests: use f64::from(i32) instead
  of `as f64` (cast_lossless).
- bench `benches()` is now >100 lines after Family 09 was wired in; allow
  too_many_lines (matches the python pymodule fn).

bindings/python/tests/test_new_indicators.py

@@ -73,6 +73,9 @@ SCALAR = [
     (ta.VerticalHorizontalFilter, (28,)),
     (ta.ZScore, (20,)),
     (ta.LinRegAngle, (14,)),
+    (ta.PercentageTrailingStop, (5.0,)),
+    (ta.StepTrailingStop, (1.0,)),
+    (ta.RenkoTrailingStop, (1.0,)),
     (ta.LaguerreRSI, (0.5,)),
     (ta.ConnorsRSI, (3, 2, 100)),
     (ta.RVIVolatility, (10,)),
@@ -199,6 +202,18 @@ CANDLE_SCALAR = {
         lambda: ta.AtrTrailingStop(14, 3.0),
         lambda ind, h, l, c, v: ind.batch(h, l, c),
     ),
+    "HiLoActivator": (
+        lambda: ta.HiLoActivator(3),
+        lambda ind, h, l, c, v: ind.batch(h, l, c),
+    ),
+    "VoltyStop": (
+        lambda: ta.VoltyStop(14, 2.0),
+        lambda ind, h, l, c, v: ind.batch(h, l, c),
+    ),
+    "YoyoExit": (
+        lambda: ta.YoyoExit(14, 2.0),
+        lambda ind, h, l, c, v: ind.batch(h, l, c),
+    ),
     "TypicalPrice": (
         lambda: ta.TypicalPrice(),
         lambda ind, h, l, c, v: ind.batch(h, l, c),
@@ -307,6 +322,10 @@ MULTI = {
         lambda: ta.ChandeKrollStop(10, 1.0, 9),
         lambda ind, h, l, c, v: ind.batch(h, l, c),
     ),
+    "DonchianStop": (
+        lambda: ta.DonchianStop(10),
+        lambda ind, h, l, c, v: ind.batch(h, l),
+    ),
     # Family 05 candle-input bands. Each entry is
     # `(factory, batch_call, output_arity, streaming_fields)` where
     # `streaming_fields` is the tuple shape returned by `update(...)`.