feat(ifc-cli): enable static file hosting in ifc-cli server

This allows ifc-cli to serve static files in addition to acting as a proxy to a dev server, for
simpler client-embedding setups. We have also updated the example app to use this hosting in
conjunction with build changes that make it easier to build both an app js file and web workers for
future IFC features

apps/ifc-example-client/README.md

@@ -16,3 +16,10 @@ commands from the iframe-coordinator project root (the parent directory of this
 `npm run start-client-example`
 
 You can then see the apps embedded in a host at http://localhost:3000/#/app1 and http://localhost:3000/#/app2
+
+### Notes
+
+There's no hot-reloading in development mode, so you'll need to refresh the page
+after making changes. The dev mode uses a rollup watcher rather than a server like
+Vite because building stand-alone web-worker modules is particularly challenging
+with Vite.

apps/ifc-example-client/client-worker.js

@@ -0,0 +1,7 @@
+// This module is a POC placeholder for a future IFC-integrated web-worker example
+
+// This doesn't work because Client references HTMLElement, which doesn't exist
+// in the worker context, but will work for a new worker client.
+// import { Client } from "iframe-coordinator/dist/client.js";
+
+console.log("Worker Started!");

apps/ifc-example-client/ifc-proxy.config.json

@@ -1,3 +1,5 @@
 {
-  "/clients/": "http://localhost:8080/"
+  "static": {
+    "/clients": "."
+  }
 }

apps/ifc-example-client/package.json

@@ -13,14 +13,15 @@
   "type": "module",
   "scripts": {
     "start": "concurrently \"npm:dev\" \"npm:start-host-shim\"",
-    "dev": "vite --port 8080",
-    "build": "vite build",
+    "dev": "rollup -c --watch",
+    "build": "rollup -c",
     "start-host-shim": "ifc-cli"
   },
   "devDependencies": {
+    "@rollup/plugin-node-resolve": "^16.0.0",
     "concurrently": "^8.2.2",
     "iframe-coordinator-cli": "file:../../packages/iframe-coordinator-cli",
-    "vite": "^5.4.2"
+    "rollup": "^4.30.1"
   },
   "dependencies": {
     "@babel/polyfill": "^7.12.1",

apps/ifc-example-client/rollup.config.js

@@ -0,0 +1,18 @@
+import { nodeResolve } from "@rollup/plugin-node-resolve";
+
+import { dirname, resolve } from "path";
+import { fileURLToPath } from "url";
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+
+export default {
+  input: [
+    resolve(__dirname, "client-app.js"),
+    resolve(__dirname, "client-worker.js"),
+  ],
+  output: {
+    preserveModules: false,
+    dir: "dist",
+  },
+  plugins: [nodeResolve()],
+};