Clarification comments in source

Author: Bart Koelman

src/JsonApiDotNetCore/Internal/Queries/Parsing/FilterParser.cs

@@ -127,6 +127,7 @@ protected ComparisonExpression ParseComparison(string operatorName)
             EatText(operatorName);
             EatSingleCharacterToken(TokenKind.OpenParen);
 
+            // Allow equality comparison of a HasOne relationship with null.
             var leftChainRequirements = comparisonOperator == ComparisonOperator.Equals
                 ? FieldChainRequirements.EndsInAttribute | FieldChainRequirements.EndsInToOne
                 : FieldChainRequirements.EndsInAttribute;

src/JsonApiDotNetCore/Internal/Queries/Parsing/QueryStringParameterScopeParser.cs

@@ -59,6 +59,7 @@ protected override IReadOnlyCollection<ResourceFieldAttribute> OnResolveFieldCha
         {
             if (chainRequirements == FieldChainRequirements.EndsInToMany)
             {
+                // The mismatch here (ends-in-to-many being interpreted as entire-chain-must-be-to-many) is intentional.
                 return ChainResolver.ResolveToManyChain(_resourceContextInScope, path, _validateSingleFieldCallback);
             }