Windows: chub get fails with ENOENT on mkdir due to forward-slash path splitting

Bug

chub get <id> fails on Windows with:

Error: Failed to load "anthropic/package": ENOENT: no such file or directory, mkdir ''
Assertion failed: !(handle->flags & UV_HANDLE_CLOSING), file src\win\async.c, line 76

Root Cause

In src/lib/cache.js, line 190:

const dir = cachedPath.substring(0, cachedPath.lastIndexOf('/'));

On Windows, cachedPath uses backslashes (e.g. C:\Users\...\.chub\sources\default\data\anthropic\docs\package\python\DOC.md), so lastIndexOf('/') returns -1, making dir an empty string ''. Then mkdirSync('', { recursive: true }) throws ENOENT.

Fix

Replace the manual string splitting with dirname() which is already imported at the top of the file:

-  const dir = cachedPath.substring(0, cachedPath.lastIndexOf('/'));
-  mkdirSync(dir, { recursive: true });
+  mkdirSync(dirname(cachedPath), { recursive: true });

dirname() from node:path correctly handles both / and \ separators.

Environment

• Windows 11
• Node.js v22
• @aisuite/chub v0.1.3

Notes

chub search and chub update work fine — only chub get is affected (when fetching from CDN for the first time, triggering the cache write path).