SIMD Refactor: Merge simd-dev into dev (#55)

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
Co-authored-by: aider (openrouter/anthropic/claude-sonnet-4) <aider@aider.chat>
Co-authored-by: Warp <agent@warp.dev>

lib/volatility/bbw/bbw.pine

@@ -0,0 +1,44 @@
+// The MIT License (MIT)
+// © mihakralj
+//@version=6
+indicator("Bollinger Band Width (BBW)", "BBW", overlay=false)
+
+//@function Calculates Bollinger Band Width as the difference between upper and lower bands
+//@param source Series to calculate Bollinger Bands from
+//@param period Lookback period for calculations
+//@param multiplier Standard deviation multiplier for band width
+//@returns BBW value representing the width between Bollinger Bands
+//@optimized for performance and dirty data
+bbw(series float source, simple int period, simple float multiplier) =>
+    if period <= 0 or multiplier <= 0.0
+        runtime.error("Period and multiplier must be greater than 0")
+    var int p = math.max(1, period), var int head = 0, var int count = 0
+    var array<float> buffer = array.new_float(p, na)
+    var float sum = 0.0, var float sumSq = 0.0
+    float oldest = array.get(buffer, head)
+    if not na(oldest)
+        sum -= oldest
+        sumSq -= oldest * oldest
+        count -= 1
+    float current_val = nz(source)
+    sum += current_val
+    sumSq += current_val * current_val
+    count += 1
+    array.set(buffer, head, current_val)
+    head := (head + 1) % p
+    float basis = nz(sum / count, source)
+    float dev = count > 1 ? multiplier * math.sqrt(math.max(0.0, sumSq / count - basis * basis)) : 0.0
+    2 * dev
+
+// ---------- Main loop ----------
+
+// Inputs
+i_period = input.int(20, "Period", minval=1)
+i_source = input.source(close, "Source")
+i_multiplier = input.float(2.0, "StdDev Multiplier", minval=0.001)
+
+// Calculation
+bbw_value = bbw(i_source, i_period, i_multiplier)
+
+// Plot
+plot(bbw_value, "BBW", color=color.yellow, linewidth=2)