fix(cli): keep classifyKtxRepoOwnership total for non-directory paths

The setup ownership guard runs before the existing not-a-directory check, so
pointing a custom/--project-dir path at a file made classifyKtxRepoOwnership
lstat `<file>/.git`, hit ENOTDIR, and throw — crashing the setup step instead
of returning the friendly "path exists and is not a directory" result.

A path that is a file (or missing) holds no git repo for ktx to avoid, so treat
ENOTDIR like ENOENT and return 'unowned'. The downstream existingFolderState
check still rejects a non-directory with its friendly message, and the
classifier no longer throws raw errno for any caller.

packages/cli/test/context/core/git.service.repo-isolation.test.ts

@@ -151,4 +151,10 @@ describe('classifyKtxRepoOwnership', () => {
     await writeFile(join(dir, '.git'), 'gitdir: ../actual.git\n', 'utf-8');
     expect(await classifyKtxRepoOwnership(dir)).toBe('foreign');
   });
+
+  it('reports unowned when the path is itself a file', async () => {
+    const filePath = join(tempDir, 'notes.txt');
+    await writeFile(filePath, 'a file, not a folder\n', 'utf-8');
+    expect(await classifyKtxRepoOwnership(filePath)).toBe('unowned');
+  });
 });