feat: better structured internal

internal/config/config.go

@@ -0,0 +1,11 @@
+package config
+
+// Arguments given to program.
+type Config struct {
+	// The source code given to the program.
+	Source Source
+	// Whether or not to print debug logs.
+	Verbose bool
+	// Whether or not to print an explanation of the reduction.
+	Explanation bool
+}