fix(semantic): add bytes operator inference for concatenation, repetition, and comparison

Add bytes type handling to TypeInferenceService.TryInferBuiltinBinaryOp
for bytes+bytes (concat), bytes*int/int*bytes (repetition), and
bytes==bytes/bytes\!=bytes (equality). Add bytes case to
OperatorValidator.SupportsOperator for __add__, __mul__, __eq__, __ne__,
and __contains__. Remove bytes_operators.skip to enable integration test.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: antonsynd

src/Sharpy.Compiler.Tests/Integration/TestFixtures/bytes_operators.skip

@@ -225,6 +225,30 @@ BinaryOperator.LessThan or BinaryOperator.LessThanOrEqual or
                 return SemanticType.Str;
         }
 
+        // Bytes operations: concatenation, repetition, equality
+        if (left is UserDefinedType { Name: BuiltinNames.Bytes } leftBytes)
+        {
+            if (right is UserDefinedType { Name: BuiltinNames.Bytes })
+            {
+                var result = op switch
+                {
+                    BinaryOperator.Add => leftBytes,
+                    BinaryOperator.Equal or BinaryOperator.NotEqual => SemanticType.Bool,
+                    _ => (SemanticType?)null
+                };
+                if (result != null) return result;
+            }
+            if (op == BinaryOperator.Multiply && TypeUtils.IsInteger(right))
+                return leftBytes;
+        }
+
+        // Bytes repetition: int * bytes
+        if (op == BinaryOperator.Multiply && TypeUtils.IsInteger(left) &&
+            right is UserDefinedType { Name: BuiltinNames.Bytes })
+        {
+            return right;
+        }
+
         // List concatenation
         if (left is GenericType { Name: BuiltinNames.List } leftList &&
             right is GenericType { Name: BuiltinNames.List } rightList)

src/Sharpy.Compiler/Semantic/TypeInferenceService.cs

@@ -1,6 +1,7 @@
 using Sharpy.Compiler.Diagnostics;
 using Sharpy.Compiler.Parser.Ast;
 using Sharpy.Compiler.Logging;
+using Sharpy.Compiler.Shared;
 
 namespace Sharpy.Compiler.Semantic.Validation;
 
@@ -239,6 +240,12 @@ private bool SupportsOperator(SemanticType type, string dunderName)
             return dunderName is DunderNames.Add or DunderNames.Mul or DunderNames.Eq or DunderNames.Ne or DunderNames.Lt or DunderNames.Le or DunderNames.Gt or DunderNames.Ge;
         }
 
+        // Bytes supports concatenation, repetition, equality, and containment
+        if (type is UserDefinedType { Name: BuiltinNames.Bytes })
+        {
+            return dunderName is DunderNames.Add or DunderNames.Mul or DunderNames.Eq or DunderNames.Ne or DunderNames.Contains;
+        }
+
         // Builtin numeric types support arithmetic operations
         if (type is BuiltinType)
         {