add own clean plugin

this only cleans up deleted files.
otherwise all files are deleted everytime, which makes HMR less useful

packages/addon-dev/src/rollup-clean-plugin.ts

@@ -0,0 +1,21 @@
+import walkSync from 'walk-sync';
+import { rmSync } from 'fs';
+import { join } from 'path';
+import type { Plugin } from 'rollup';
+
+export default function clean(): Plugin {
+  return {
+    name: 'clean',
+    writeBundle(options, bundle) {
+      const files = walkSync(options.dir!, {
+        globs: ['*/**'],
+        directories: false,
+      });
+      for (const file of files) {
+        if (!bundle[file]) {
+          rmSync(join(options.dir!, file));
+        }
+      }
+    },
+  };
+}

packages/addon-dev/src/rollup.ts

@@ -2,11 +2,10 @@ import { default as hbs } from './rollup-hbs-plugin';
 import { default as gjs } from './rollup-gjs-plugin';
 import { default as publicEntrypoints } from './rollup-public-entrypoints';
 import { default as appReexports } from './rollup-app-reexports';
-import type { Options as DelOptions } from 'rollup-plugin-delete';
-import { default as clean } from 'rollup-plugin-delete';
 import { default as keepAssets } from './rollup-keep-assets';
 import { default as dependencies } from './rollup-addon-dependencies';
 import { default as publicAssets } from './rollup-public-assets';
+import { default as clean } from './rollup-clean-plugin';
 import type { Plugin } from 'rollup';
 
 export class Addon {
@@ -62,9 +61,9 @@ export class Addon {
   }
 
   // By default rollup does not clear the output directory between builds. This
-  // does that.
-  clean(options: DelOptions) {
-    return clean({ targets: `${this.#destDir}/*`, ...options });
+  // does that. It only deletes files that are not part of the generated bundle
+  clean() {
+    return clean();
   }
 
   // V2 Addons are allowed to contain imports of .css files. This tells rollup