[Fix] 修复无法调用类函数的问题

[Feat] Context merge功能
[Feat] VSCode 拓展现已更为 fig-vscode.

include/evaluator.hpp

@@ -15,6 +15,7 @@ namespace Fig
     class EvaluatorError final : public AddressableError
     {
     public:
+        const char* errorName = errName;
         virtual FString toString() const override
         {
             std::string msg = std::format("[Eve: {}] {} in [{}] {}", errName, std::string(this->message.begin(), this->message.end()), this->src_loc.file_name(), this->src_loc.function_name());
@@ -27,6 +28,11 @@ namespace Fig
             AddressableError(_msg, aai.line, aai.column, loc)
         {
         }
+
+        virtual FString getErrorType() const override
+        {
+            return FString("[Eval]" + std::string(errorName));
+        }
     };
     struct StatementResult
     {