refactor: move dwn wasm build to pkg directory

pkg/dwn/sw.js

@@ -0,0 +1,16 @@
+importScripts(
+  "https://cdn.jsdelivr.net/gh/golang/go@go1.22.5/misc/wasm/wasm_exec.js",
+  "https://cdn.jsdelivr.net/gh/nlepage/go-wasm-http-server@v1.1.0/sw.js",
+);
+
+registerWasmHTTPListener("/app.wasm");
+
+// Skip installed stage and jump to activating stage
+self.addEventListener("install", (event) => {
+  event.waitUntil(skipWaiting());
+});
+
+// Start controlling clients as soon as the SW is activated
+self.addEventListener("activate", (event) => {
+  event.waitUntil(clients.claim());
+});