docs: remove C# Implementation Considerations sections, clean up temp scripts, reorganize test files

- Remove 'C# Implementation Considerations' sections from 34 indicator .md files
- Delete 29 temp PowerShell scripts (_fix_mojibake.ps1, _hex_scan.ps1, etc.)
- Move test files into tests/ subdirectories for consistent project structure
- Add trader-focused bullet points to indicator documentation

lib/trends_IIR/htit/tests/Htit.Quantower.Tests.cs

@@ -0,0 +1,40 @@
+using TradingPlatform.BusinessLayer;
+
+namespace QuanTAlib.Quantower.Tests;
+
+public class HtitIndicatorTests
+{
+    [Fact]
+    public void Indicator_Initializes_Correctly()
+    {
+        var indicator = new HtitIndicator();
+        indicator.Initialize();
+        Assert.Equal("HTIT - Ehlers Hilbert Transform Instantaneous Trend", indicator.Name);
+        Assert.StartsWith("HTIT", indicator.ShortName, StringComparison.Ordinal);
+        Assert.Contains("Close", indicator.ShortName, StringComparison.Ordinal);
+        Assert.Equal(0, HtitIndicator.MinHistoryDepths);
+        Assert.Single(indicator.LinesSeries);
+    }
+
+    [Fact]
+    public void Indicator_Updates_Correctly()
+    {
+        var indicator = new HtitIndicator();
+        indicator.Initialize();
+
+        // Warmup
+        for (int i = 0; i < 100; i++)
+        {
+            var time = DateTime.UtcNow.AddMinutes(i);
+            indicator.HistoricalData.AddBar(time, 100 + i, 100 + i, 100 + i, 100 + i);
+
+            var args = new UpdateArgs(UpdateReason.NewBar);
+            indicator.ProcessUpdate(args);
+        }
+
+        // Check if value is set (should be non-zero after warmup)
+        var result = indicator.LinesSeries[0].GetValue();
+        Assert.NotEqual(0, result);
+        Assert.False(double.IsNaN(result));
+    }
+}