Use rollup's addWatchFile API to mark dependencies

This solves a bunch of watch-mode (not) rebuilding issues; as a
general rule everytime we probe or read from the file system we
should at least consider whether such an annotation is needed.

Unfortunately this package doesn't appear to be tested currently,
but I have applied the same patch locally and it appears to be
working fine.

packages/addon-dev/src/rollup-addon-dependencies.ts

@@ -11,8 +11,8 @@ const compilationModules = new Set(
   templateCompilationModules.map((m) => m.module)
 );
 
-function resolvableDependencies() {
-  let deps = new Set();
+function resolvableDependencies(): Set<string> {
+  let deps = new Set<string>();
   let pkg = readJsonSync('package.json');
   if (pkg.dependencies) {
     for (let name of Object.keys(pkg.dependencies)) {
@@ -28,11 +28,16 @@ function resolvableDependencies() {
 }
 
 export default function emberExternals(): Plugin {
-  let deps = resolvableDependencies();
+  let deps: Set<string>;
 
   return {
     name: 'ember-externals',
 
+    buildStart() {
+      this.addWatchFile('package.json');
+      deps = resolvableDependencies();
+    },
+
     async resolveId(source) {
       let pkgName = packageName(source);
       if (!pkgName) {

packages/addon-dev/src/rollup-keep-assets.ts

@@ -14,6 +14,12 @@ export default function keepAssets({
   return {
     name: 'copy-assets',
 
+    // Prior to https://github.com/rollup/rollup/pull/5270, we cannot call this
+    // from within `generateBundle`
+    buildStart() {
+      this.addWatchFile(from);
+    },
+
     // imports of assets should be left alone in the source code. This can cover
     // the case of .css as defined in the embroider v2 addon spec.
     async resolveId(source, importer, options) {

packages/addon-dev/src/rollup-public-assets.ts

@@ -11,6 +11,13 @@ export default function publicAssets(
 
   return {
     name: 'public-assets-bundler',
+
+    // Prior to https://github.com/rollup/rollup/pull/5270, we cannot call this
+    // from within `generateBundle`
+    buildStart() {
+      this.addWatchFile(path);
+    },
+
     generateBundle() {
       let pkg = readJsonSync('package.json');
       const filenames = walkSync(path, {

packages/addon-dev/src/rollup-public-entrypoints.ts

@@ -15,6 +15,8 @@ export default function publicEntrypoints(args: {
   return {
     name: 'addon-modules',
     async buildStart() {
+      this.addWatchFile(args.srcDir);
+
       let matches = walkSync(args.srcDir, {
         globs: [...args.include, '**/*.hbs', '**/*.ts', '**/*.gts', '**/*.gjs'],
       });