Return an IdentifierTypeSyntax in detectExpressionType

Not quite sure, but this returned a `MemberExpressionType` when using
the literal, maybe that changed in 600?

Author: helje5

Sources/ManagedModelMacros/Utilities/ExpressionType.swift

@@ -8,6 +8,10 @@ import SwiftSyntax
 extension ExprSyntax {
 
   func detectExpressionType() -> TypeSyntax? {
+    guard let idType = detectExpressionTypeName() else { return nil }
+    return TypeSyntax(IdentifierTypeSyntax(name: .identifier(idType)))
+  }
+  func detectExpressionTypeName() -> String? {
     // TODO: detect base types and such
     // - check function expressions, like:
     //   - `Data()`?
@@ -18,7 +22,8 @@ extension ExprSyntax {
       case .integerLiteralExpr : return "Swift.Int"
       case .floatLiteralExpr   : return "Swift.Double"
       case .booleanLiteralExpr : return "Swift.Bool"
-      default: break
+      default:
+        break
     }
 
     return nil