feat: Family 06 Trend-Strength - 5 new directional/random-walk indicators (#44)

* feat(adxr): add Wilder Average Directional Movement Index Rating

ADXR is the trend-strength smoother Wilder published alongside ADX in
*New Concepts in Technical Trading Systems* (1978):

    ADXR_t = (ADX_t + ADX_{t - (period - 1)}) / 2

The lookback length is the same period that feeds the underlying ADX.
Because the older ADX is period - 1 bars stale, ADXR responds more
slowly than ADX and is the canonical metric for comparing
trend-strength across instruments.

Implementation reuses the existing wickra_core::Adx engine plus a
period-length ring of past ADX values; warmup is 3 * period - 1
(41 for period = 14). Bindings: Python PyAdxr (PyArray1 batch),
Node AdxrNode (number scalar), WASM WasmAdxr. Fuzz target covers
the candle-input path. Python + Node streaming-vs-batch tests
parametrised, plus a pure-uptrend reference value (ADXR == 100
when ADX saturates at 100). Criterion bench added under crates/
wickra/benches/indicators.rs.

README family table and indicator counter updated (71 -> 72).

* feat(rwi): add Mike Poulos Random Walk Index

RWI compares actual price displacement to what a random walk would
produce over the same horizon: for each lookback i in [2, period],

    RWI_High_t(i) = (high_t - low_{t-i+1}) / (ATR_i(t) * sqrt(i))
    RWI_Low_t(i)  = (high_{t-i+1} - low_t) / (ATR_i(t) * sqrt(i))

Per-bar output is the maximum across lookbacks for each direction;
a reading > 1 means the trend beats random-walk noise, > 2 is the
typical strong-trend threshold. Multi-output (high, low). period
must be >= 2 (the shortest meaningful lookback); period < 2 returns
InvalidPeriod. Warmup = period (e.g. 14 for the standard default).

Bindings: Python PyRwi (PyArray2 shape (n, 2)), Node RwiNode +
RwiValue struct, WASM WasmRwi (Object/Reflect for update,
Float64Array interleaved for batch). Fuzz target adds the candle
input case. Python parametric streaming-vs-batch test and pure
uptrend reference test (RWI_High dominates RWI_Low and exceeds 1).
Node parametric streaming-vs-interleaved-batch test. Criterion
bench under crates/wickra/benches/indicators.rs.

README family table and indicator counter updated (72 -> 73).

* feat(tii): add M.H. Pee Trend Intensity Index

TII is a [0, 100] oscillator that asks 'what fraction of the recent
SMA deviations are positive?'. The construction is

    dev_t  = close_t - SMA(close, sma_period)_t
    SD_pos = sum of positive dev_t over the last dev_period bars
    SD_neg = sum of |negative dev_t| over the last dev_period bars
    TII    = 100 * SD_pos / (SD_pos + SD_neg)

Saturates at 100 on a pure uptrend (every close above the lagging
SMA), at 0 on a pure downtrend, and returns the neutral mid-point 50
on a perfectly flat window. The output is clamped to [0, 100] as
the rolling-sum subtraction loop can accumulate a few ULP of error
on long histories. Canonical Pee parameters (sma_period=60,
dev_period=30) wired as Python defaults; warmup is
sma_period + dev_period - 1 (89 for the defaults).

Bindings: Python PyTii (PyArray1 batch), Node TiiNode (scalar
update + batch), WASM WasmTii via the two-arg wasm_scalar_indicator!
macro. Fuzz target adds the scalar path. Python parametric
streaming-vs-batch test plus pure-uptrend (TII == 100) and
flat-market (TII == 50) reference tests. Node parametric
streaming-vs-batch test. Criterion bench under crates/wickra/
benches/indicators.rs.

README family table and indicator counter updated (73 -> 74).

* feat(kst): add Pring Know Sure Thing oscillator

KST is Martin Pring's long-horizon momentum gauge: four smoothed
rate-of-change components combined with fixed weights (1, 2, 3, 4),
plus an SMA signal line.

    RCMA_i = SMA(ROC(close, roc_i), sma_i)        for i in 1..=4
    KST    = 1*RCMA_1 + 2*RCMA_2 + 3*RCMA_3 + 4*RCMA_4
    Signal = SMA(KST, signal_period)

Kst::classic() exposes Pring's recommended parameter set
(roc = (10, 15, 20, 30), sma = (10, 10, 10, 15), signal = 9);
warmup = max(roc_i + sma_i) + signal_period - 1 (53 for the classic
parameters). All four parallel branches are fed unconditionally so
they warm in lock-step.

Bindings: Python PyKst (PyArray2 shape (n, 2)) with a KST.classic()
staticmethod, Node KstNode + KstValue with a KST.classic() factory,
WASM WasmKst with both new(...) and classic() constructors plus
Object/Reflect for update and Float64Array for batch. Fuzz target
adds the scalar multi-output path. Python tests gain a new
MULTI_SCALAR section parametric over scalar-input/multi-output
indicators, plus a classic-on-constant-series reference test. Node
tests gain a KST entry in the multi-output section. Criterion
benchmark added under crates/wickra/benches/indicators.rs.

README family table and indicator counter updated (74 -> 75).

* feat(wave-trend): add LazyBear Wave Trend Oscillator

Two-line mean-reverting momentum gauge built from the typical price
and three cascaded EMAs:

    ap   = (high + low + close) / 3
    esa  = EMA(ap, channel_period)
    d    = EMA(|ap - esa|, channel_period)
    ci   = (ap - esa) / (0.015 * d)
    wt1  = EMA(ci, average_period)
    wt2  = SMA(wt1, signal_period)

WaveTrend::classic() exposes LazyBear's defaults
(channel = 10, average = 21, signal = 4); warmup is
2 * channel_period + average_period + signal_period - 3 (42 for the
classic defaults). On a perfectly flat market the SMA-seeded EMA
introduces a single-ULP drift between ap and esa, which on a tiny d
would make the ratio explode to -1/0.015 = -66.67; a price-scaled
flat-tolerance guard (d <= 16 * EPSILON * max(|esa|, 1)) collapses
the channel index to 0 in that regime so both lines remain at zero.

Bindings: Python PyWaveTrend (PyArray2 shape (n, 2)) with a
WaveTrend.classic() staticmethod, Node WaveTrendNode + WaveTrendValue
with a WaveTrend.classic() factory, WASM WasmWaveTrend with both
new(...) and classic() constructors. Fuzz target adds the candle
multi-output path (sorted alphabetically). Python parametric
streaming-vs-batch test plus a flat-market reference test. Node
parametric streaming-vs-interleaved-batch test. Criterion bench
under crates/wickra/benches/indicators.rs.

README family table and indicator counter updated (75 -> 76).

* fix(family-06): re-add KST::classic() factory + drop dup fuzz block

Family-06 PR's tests call ta.KST.classic() / wickra.KST.classic() — main's
KST binding shipped without the static factory. Add classic() in Python
(staticmethod) and Node (napi factory); WASM already had it. Also drop the
duplicate Kst::classic().unwrap() block in fuzz/indicator_update.rs that
the merge left behind (main's API no longer returns Result).

* test(rwi): drop dead count==0 guard

The loop `for i in 2..=period` makes `count = tr_end - tr_start = i - 1`
which is always >= 1, so the `if count == 0 { continue; }` branch was
unreachable defensive code that codecov flagged on the family-06 PR.

crates/wickra-core/src/indicators/mod.rs

@@ -8,6 +8,7 @@ mod acceleration_bands;
 mod accelerator_oscillator;
 mod adl;
 mod adx;
+mod adxr;
 mod alligator;
 mod alma;
 mod apo;
@@ -77,6 +78,7 @@ mod rogers_satchell;
 mod rsi;
 mod rvi;
 mod rvi_volatility;
+mod rwi;
 mod sma;
 mod smi;
 mod smma;
@@ -89,6 +91,7 @@ mod stochastic;
 mod super_trend;
 mod t3;
 mod tema;
+mod tii;
 mod trima;
 mod trix;
 mod true_range;
@@ -104,6 +107,7 @@ mod vpt;
 mod vwap;
 mod vwap_stddev_bands;
 mod vwma;
+mod wave_trend;
 mod weighted_close;
 mod williams_r;
 mod wma;
@@ -116,6 +120,7 @@ pub use acceleration_bands::{AccelerationBands, AccelerationBandsOutput};
 pub use accelerator_oscillator::AcceleratorOscillator;
 pub use adl::Adl;
 pub use adx::{Adx, AdxOutput};
+pub use adxr::Adxr;
 pub use alligator::{Alligator, AlligatorOutput};
 pub use alma::Alma;
 pub use apo::Apo;
@@ -185,6 +190,7 @@ pub use rogers_satchell::RogersSatchellVolatility;
 pub use rsi::Rsi;
 pub use rvi::Rvi;
 pub use rvi_volatility::RviVolatility;
+pub use rwi::{Rwi, RwiOutput};
 pub use sma::Sma;
 pub use smi::Smi;
 pub use smma::Smma;
@@ -197,6 +203,7 @@ pub use stochastic::{Stochastic, StochasticOutput};
 pub use super_trend::{SuperTrend, SuperTrendOutput};
 pub use t3::T3;
 pub use tema::Tema;
+pub use tii::Tii;
 pub use trima::Trima;
 pub use trix::Trix;
 pub use true_range::TrueRange;
@@ -212,6 +219,7 @@ pub use vpt::VolumePriceTrend;
 pub use vwap::{RollingVwap, Vwap};
 pub use vwap_stddev_bands::{VwapStdDevBands, VwapStdDevBandsOutput};
 pub use vwma::Vwma;
+pub use wave_trend::{WaveTrend, WaveTrendOutput};
 pub use weighted_close::WeightedClose;
 pub use williams_r::WilliamsR;
 pub use wma::Wma;