Bump version to 0.2.1

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: queelius

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "dagshell"
-version = "0.2.0"
+version = "0.2.1"
 description = "A virtual POSIX filesystem with content-addressable DAG structure"
 readme = "README.md"
 requires-python = ">=3.8"