feat: update contains and add test cases

packages/file-graph/file.js

@@ -2,7 +2,7 @@ import { basename } from './utils.js'
 
 export default class File {
   constructor({ path, type, discovered }) {
-    this.path = path
+    this.path = path.trimEnd('/')
     this.name = basename(path)
     this.type = type
     this.discovered = discovered
@@ -13,6 +13,9 @@ export default class File {
   }
 
   contains(file) {
-    return this.isDirectory() && file.path.startsWith(this.path)
+    if (!this.isDirectory()) return false
+    if (this.path === file.path) return true
+    const parentPath = this.path.endsWith('/') ? this.path : `${this.path}/`
+    return file.path.startsWith(parentPath)
   }
 }