fix: Using covariant interface for IParser and IParseResult.

Rename CanonSharp.Common to CanonSharp.Pascal.

CanonSharp.Combinator/Text/StringParser.cs

@@ -11,7 +11,7 @@ namespace CanonSharp.Combinator.Text;
 /// <param name="comparison">字符串比较模式</param>
 public class StringParser(string except, StringComparison comparison) : PrimitiveParser<char, string>
 {
-    protected override ParseResult<char, string> Run<TState>(TState state)
+    protected override IParseResult<char, string> Run<TState>(TState state)
     {
         TState[] states = state.AsEnumerable<char, TState>().Take(except.Length).ToArray();
         string actual = new(states.Select(x => x.Current).ToArray());