feat: separate solver logic into dedicated web worker, improve toast notifications

src/workers/Solver.worker.js

@@ -0,0 +1,58 @@
+import { DeepCube } from "../utils/DeepCube.js";
+import { KociembaSolver } from "../utils/solvers/KociembaSolver.js";
+import { BeginnerSolver } from "../utils/solvers/BeginnerSolver.js";
+
+let isKociembaReady = false;
+
+// Defer heavy initialization to allow the worker to be responsive initially
+setTimeout(() => {
+  console.log("[SolverWorker] Kociemba solver initialization");
+  console.time("[SolverWorker] Kociemba solver initialization");
+  KociembaSolver.init();
+  console.timeEnd("[SolverWorker] Kociemba solver initialization");
+  isKociembaReady = true;
+  postMessage({ type: "INIT_DONE" });
+}, 50);
+
+self.onmessage = (e) => {
+  const { type, payload } = e.data;
+
+  if (type === "SOLVE") {
+    const { solverType, cubeState } = payload;
+
+    if (solverType === "kociemba" && !isKociembaReady) {
+      postMessage({ type: "SOLVE_ERROR", payload: "wait for initialize solver" });
+      return;
+    }
+
+    try {
+      // Reconstruct DeepCube state from payload
+      const dc = new DeepCube(
+        new Int8Array(cubeState.cp),
+        new Int8Array(cubeState.co),
+        new Int8Array(cubeState.ep),
+        new Int8Array(cubeState.eo)
+      );
+
+      let solution = [];
+      if (solverType === "kociemba") {
+        const solver = new KociembaSolver(dc);
+        solution = solver.solve();
+      } else if (solverType === "beginner") {
+        const solver = new BeginnerSolver(dc);
+        solution = solver.solve();
+      } else {
+        throw new Error(`Unknown solver type: ${solverType}`);
+      }
+
+      postMessage({
+        type: "SOLVE_RESULT",
+        payload: solution,
+      });
+    } catch (err) {
+      console.error("[SolverWorker] Solve error:", err);
+      postMessage({ type: "SOLVE_ERROR", payload: err.message });
+      postMessage({ type: "SOLVE_RESULT", payload: [] });
+    }
+  }
+};