FileTree component was not passing baseDir to the file API, causing
it to fall back to restricting access to the home directory. On
Windows, projects on a different drive (e.g., D:\) were blocked
with 403.
Changes:
- FileTree now passes workingDirectory as baseDir parameter
- File API routes no longer require baseDir to be under homeDir
(allows cross-drive access on Windows)
- Still prevents using filesystem root as baseDir for safety
- Add isRootPath() utility for root path detection
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>