Move @parity/resolc from js-revive (#296)

- Move npm package from paritytech/js-revive 
- Rename package to `@parity/resolc`

js/emscripten/build.js

@@ -0,0 +1,54 @@
+const fs = require("fs");
+const path = require("path");
+const { minify } = require("terser");
+
+const SOLJSON_URI =
+  "https://binaries.soliditylang.org/wasm/soljson-v0.8.29+commit.ab55807c.js";
+const RESOLC_WASM_URI =
+  process.env.RELEASE_RESOLC_WASM_URI || "http://127.0.0.1:8080/resolc.wasm";
+const RESOLC_WASM_TARGET_DIR = path.join(
+  __dirname,
+  "../../target/wasm32-unknown-emscripten/release",
+);
+const RESOLC_JS = path.join(RESOLC_WASM_TARGET_DIR, "resolc.js");
+const RESOLC_WEB_JS = path.join(RESOLC_WASM_TARGET_DIR, "resolc_web.js");
+
+const resolcJs = fs.readFileSync(RESOLC_JS, "utf-8");
+
+const packedJsContent = `
+if (typeof importScripts === "function") {
+  importScripts("${SOLJSON_URI}");
+
+  var moduleArgs = {
+    wasmBinary: (function () {
+      var xhr = new XMLHttpRequest();
+      xhr.open("GET", "${RESOLC_WASM_URI}", false);
+      xhr.responseType = "arraybuffer";
+      xhr.send(null);
+      return new Uint8Array(xhr.response);
+    })(),
+    soljson: Module
+  };
+} else {
+  console.log("Not a WebWorker, skipping Soljson and WASM loading.");
+}
+
+${resolcJs}
+
+createRevive = createRevive.bind(null, moduleArgs);
+`;
+
+minify(packedJsContent)
+  .then((minifiedJs) => {
+    if (minifiedJs.error) {
+      console.error("Error during minification:", minifiedJs.error);
+      process.exit(1);
+    }
+
+    fs.writeFileSync(RESOLC_WEB_JS, minifiedJs.code, "utf-8");
+    console.log(`Combined script written to ${RESOLC_WEB_JS}`);
+  })
+  .catch((err) => {
+    console.error("Minification failed:", err);
+    process.exit(1);
+  });