breaking: Use only esm modules for lib/* packages and remove esm2umd dependency

.github/workflows/publish.yml

@@ -38,11 +38,9 @@ jobs:
           npm test
           cd lib/loader
           npm version "$VERSION" --no-git-tag-version
-          npm run build
           npm test
           cd ../rtrace
           npm version "$VERSION" --no-git-tag-version
-          npm run build
           npm test
           cd ../..
         fi

lib/loader/README.md

@@ -7,7 +7,7 @@ A tiny module loader that makes working with AssemblyScript modules as convenien
 ## Example
 
 ```ts
-import loader from "@assemblyscript/loader"; // or require
+import loader from "@assemblyscript/loader";
 loader.instantiate(
   // Binary to instantiate
   fetch("optimized.wasm"), // or fs.readFileSync
@@ -33,12 +33,17 @@ npm install --save @assemblyscript/loader
 On the web:
 
 ```html
-<!-- ESM -->
 <script type="module" src="https://cdn.jsdelivr.net/npm/@assemblyscript/loader/index.js"></script>
-<!-- UMD -->
-<script src="https://cdn.jsdelivr.net/npm/@assemblyscript/loader/umd/index.js"></script>
 ```
 
+The package is ESM-only. From CommonJS, load it with a dynamic import:
+
+```js
+const loader = (await import("@assemblyscript/loader")).default;
+```
+
+Node.js 20.19+ and 22.12+ also accept a plain `require` of an ES module.
+
 ## Usage
 
 One task the loader does not perform is to implicitly translate between WebAssembly pointers and JavaScript objects, and that's where the mixed in utility comes into play. For example, if one has

lib/loader/index.d.ts

@@ -122,3 +122,12 @@ export declare function demangle<T extends Record<string,unknown>>(
   exports: Record<string,unknown>,
   extendedExports?: Record<string,unknown>
 ): T;
+
+declare const _default: {
+  instantiate: typeof instantiate,
+  instantiateSync: typeof instantiateSync,
+  instantiateStreaming: typeof instantiateStreaming,
+  demangle: typeof demangle
+};
+
+export default _default;