v0.2.1

What's changed

• Added Ghostty-style project opening through the Termy CLI: termy /path/to/project and termy --working-directory /path/to/project.
• Wired startup argument handling so launched Termy windows use the requested working directory.
• Continued libtermy/FFI work by exposing runtime/config data needed by embedders and updating the docs.
• Bumped the app and CLI packages to 0.2.1.

Validation

• cargo fmt
• cargo test -q -p termy_cli open_
• cargo test -q -p termy startup_arguments
• cargo check --workspace