fix(build): tighten BuildTarget enum parsing

Author: JMartinezRuiz

MCPForUnity/Editor/Tools/Build/BuildTargetMapping.cs

@@ -28,8 +28,11 @@ public static bool TryResolveBuildTarget(string name, out BuildTarget target)
                 case "uwp": target = BuildTarget.WSAPlayer; return true;
                 case "tvos": target = BuildTarget.tvOS; return true;
                 default:
-                    if (Enum.TryParse(name, true, out target))
+                    if (TryParseDefinedBuildTarget(name, out target))
+                    {
                         return true;
+                    }
+
                     target = default;
                     return false;
             }
@@ -100,7 +103,7 @@ public static string GetUnknownBuildTargetMessage(string name)
         private static string GetValidTargetsList()
         {
             string validTargets = "windows64, osx, linux64, android, ios, webgl, uwp, tvos";
-            if (Enum.TryParse(VisionOSName, true, out BuildTarget _))
+            if (TryParseDefinedBuildTarget(VisionOSName, out _))
             {
                 validTargets += ", visionos";
             }
@@ -113,6 +116,18 @@ private static bool IsVisionOSTarget(BuildTarget target)
             return string.Equals(target.ToString(), VisionOSName, StringComparison.OrdinalIgnoreCase);
         }
 
+        private static bool TryParseDefinedBuildTarget(string name, out BuildTarget target)
+        {
+            target = default;
+            if (int.TryParse(name, out _))
+            {
+                return false;
+            }
+
+            return Enum.TryParse(name, true, out target)
+                && Enum.IsDefined(typeof(BuildTarget), target);
+        }
+
         public static string GetDefaultOutputPath(BuildTarget target, string productName)
         {
             string basePath = $"Builds/{target}";

TestProjects/UnityMCPTests/Assets/Tests/EditMode/Tools/BuildTargetMappingTests.cs

@@ -18,6 +18,12 @@ public void TryResolveBuildTarget_KnownAliasesResolve(string name, BuildTarget e
             Assert.AreEqual(expected, target);
         }
 
+        [Test]
+        public void TryResolveBuildTarget_NumericInputDoesNotResolve()
+        {
+            Assert.IsFalse(BuildTargetMapping.TryResolveBuildTarget("5", out _));
+        }
+
         [Test]
         public void TryResolveNamedBuildTarget_UnknownTargetListsOnlyAvailableTargets()
         {
@@ -46,10 +52,9 @@ public void TryResolveNamedBuildTarget_VisionOSUnavailableReturnsHelpfulError()
             if (visionOSAvailable)
             {
                 Assert.IsTrue(BuildTargetMapping.TryResolveBuildTarget("visionos", out _));
-                if (error != null)
-                {
-                    StringAssert.Contains("VisionOS", error);
-                }
+                Assert.IsTrue(
+                    error == null || error.Contains("VisionOS"),
+                    $"Expected no error or a VisionOS-specific error, got: {error}");
             }
             else
             {