Enhance code quality and stability across various modules

- Updated .coderabbit.yaml to exclude additional file types from reviews, improving the focus on relevant code changes.
- Modified scanner.sh to handle test failures more gracefully, ensuring that analysis stops on test failures and improving logging.
- Improved sonarscanner.sh to ensure build and test failures are properly reported, enhancing CI reliability.
- Refined SimdExtensions.cs documentation for clarity on variance calculation methods.
- Cleaned up TSeries.Tests.cs by simplifying the test structure and ensuring proper namespace usage.
- Fixed potential issues in tseries.cs by ensuring correct handling of DateTime values.
- Enhanced CsvFeed.cs to improve error handling during CSV parsing, ensuring robustness against malformed data.
- Updated GBM.cs to correctly calculate volume in the current bar, ensuring accurate simulation.
- Adjusted index.html to use globalThis for better compatibility across environments.
- Refined quantalib.csproj to exclude unnecessary files from compilation, streamlining the build process.
- Added comprehensive tests for the Mama class to ensure correct behavior during updates and state management.
- Improved error handling in various trend classes (Kama, Dema, Ema, T3, Tema, Wma) to ensure NaN values are managed correctly.
- Removed redundant Mama.Repro.Tests.cs file and consolidated tests into Mama.Tests.cs for better organization.
- Enhanced T3 and Tema classes to maintain state integrity during updates, particularly with NaN values.

lib/trends/conv/Conv.cs

@@ -49,6 +49,8 @@ public sealed class Conv : ITValuePublisher
         Array.Copy(kernel, _kernel, _period);
         _buffer = new RingBuffer(_period);
         Name = $"Conv({_period})";
+        _lastValidValue = double.NaN;
+        _p_lastValidValue = double.NaN;
     }
 
     public Conv(ITValuePublisher source, double[] kernel) : this(kernel)
@@ -154,7 +156,7 @@ public sealed class Conv : ITValuePublisher
         }
         else
         {
-            _lastValidValue = 0;
+            _lastValidValue = double.NaN;
         }
 
         _buffer.Clear();
@@ -516,7 +518,7 @@ public sealed class Conv : ITValuePublisher
         // Use stackalloc for small kernels to avoid heap allocation
         Span<double> window = period <= 256 ? stackalloc double[period] : new double[period];
 
-        double lastValid = 0;
+        double lastValid = double.NaN;
         int windowIdx = 0; // Points to where the NEXT value goes (circular)
         int count = 0;
 
@@ -563,8 +565,8 @@ public sealed class Conv : ITValuePublisher
     public void Reset()
     {
         _buffer.Clear();
-        _lastValidValue = 0;
-        _p_lastValidValue = 0;
+        _lastValidValue = double.NaN;
+        _p_lastValidValue = double.NaN;
         _head = 0;
         Last = default;
     }