test(cli): update postinstall-wrapper mock to export FileSystemError

The previous commit swapped InputError → FileSystemError in
postinstall-wrapper.mts but left the test's vi.mock factory still
exporting InputError, so the source couldn't resolve its
FileSystemError import under vitest:

  [vitest] No "FileSystemError" export is defined on the
  ".../src/utils/error/errors.mts" mock

Replace the mock's InputError stub with a FileSystemError stub that
matches the real class's shape (path, code, recovery) so the source
code resolves correctly. The existing regex assertion on the error
message is unaffected.

Author: jdalton

packages/cli/test/unit/commands/wrapper/postinstall-wrapper.test.mts

@@ -61,10 +61,19 @@ vi.mock('../../../../src/commands/install/setup-tab-completion.mts', () => ({
 }))
 vi.mock('../../../../src/utils/error/errors.mts', () => ({
   getErrorCause: vi.fn(e => e?.message || String(e)),
-  InputError: class InputError extends Error {
-    constructor(message: string) {
+  FileSystemError: class FileSystemError extends Error {
+    public readonly path?: string | undefined
+    public readonly code?: string | undefined
+    public readonly recovery: string[] = []
+    constructor(
+      message: string,
+      path?: string | undefined,
+      code?: string | undefined,
+    ) {
       super(message)
-      this.name = 'InputError'
+      this.name = 'FileSystemError'
+      this.path = path
+      this.code = code
     }
   },
 }))