feat: Use emoji to mark sat and unsat leafes

src/dpll-grapher.ts

@@ -48,7 +48,11 @@ export function dpllAlgoStepNodesToTree(
     ' "| N' +
     myCounter +
     '["' +
-    termString +
+    (startNode.stepTaken === "Unsatisfiable"
+      ? "❌"
+      : startNode.stepTaken === "Satisfiable"
+      ? "✅"
+      : termString) +
     '"]';
   const childrenArrows = startNode.children
     .map((c) => dpllAlgoStepNodesToTree(c, termString, myCounter))