wip: replace packages with pure files

packages/game/condition/FileMatcher.ts

@@ -0,0 +1,11 @@
+import { IFileExistenceInput, IFileExistenceChecker } from '../schema'
+
+export async function checkFiles(
+  checker: IFileExistenceChecker,
+  files: IFileExistenceInput[]
+) {
+  const existences = await Promise.all(
+    files.map((file) => checker.exists(file))
+  )
+  return existences.every((exists, index) => exists === files[index].exists)
+}