fix: use HashSet<string> for assembly deduplication in ArchLoader

Replace List<AssemblyNameReference> with HashSet<string> keyed by
FullName for tracking processed assemblies. The previous approach
used List.Contains with reference equality on AssemblyNameReference
objects, which could fail to detect duplicates when different
reference instances point to the same assembly.

Signed-off-by: Alexander Linne <alexander.linne@tngtech.com>

Author: alexanderlinne

ArchUnitNET/Loader/ArchLoader.cs

@@ -125,7 +125,7 @@ private void LoadModule(
                     fileName,
                     new ReaderParameters { AssemblyResolver = _assemblyResolver }
                 );
-                var processedAssemblies = new List<AssemblyNameReference> { module.Assembly.Name };
+                var processedAssemblies = new HashSet<string> { module.Assembly.Name.FullName };
                 var resolvedModules = new List<ModuleDefinition>();
                 _assemblyResolver.AddLib(module.Assembly);
                 _archBuilder.AddAssembly(module.Assembly, false);
@@ -144,7 +144,7 @@ private void LoadModule(
                     {
                         try
                         {
-                            processedAssemblies.Add(assemblyReference);
+                            processedAssemblies.Add(assemblyReference.FullName);
                             _assemblyResolver.AddLib(assemblyReference);
                             if (includeDependencies)
                             {
@@ -176,17 +176,17 @@ private void LoadModule(
 
         private void AddReferencedAssembliesRecursively(
             AssemblyNameReference currentAssemblyReference,
-            ICollection<AssemblyNameReference> processedAssemblies,
+            ICollection<string> processedAssemblies,
             List<ModuleDefinition> resolvedModules,
             FilterFunc filterFunc
         )
         {
-            if (processedAssemblies.Contains(currentAssemblyReference))
+            if (processedAssemblies.Contains(currentAssemblyReference.FullName))
             {
                 return;
             }
 
-            processedAssemblies.Add(currentAssemblyReference);
+            processedAssemblies.Add(currentAssemblyReference.FullName);
             try
             {
                 _assemblyResolver.AddLib(currentAssemblyReference);