* fix(cli): save screenshots to tmp dir when no path provided
Instead of outputting base64 to stdout (which is not useful for most CLI use cases),
screenshots without a path now save to ~/.agent-browser/tmp/screenshots/ with a
generated filename and return the path.
This makes the behavior more ergonomic for AI agents and CLI users alike.
* cleanup
* cleanup
* just revert the cargo.lock version for now
* refactor: extract getAppDir() from getSocketDir()
* docs: improve screenshot help text consistency