v0.6.0

• New "nexora join" command redeems an organization invite in one step: it creates or signs in your account, pairs this terminal, and saves the instance, with no manual login.
• The install one-liner now takes --join --url (or the NEXORA_JOIN_TOKEN and NEXORA_URL environment variables), so an admin can share a single copy-paste command that installs the CLI and connects it.
• The installer adds the binary to your shell PATH (.zshrc, .bashrc or .profile) and, when a join token is present, runs the join for you and points you at your instance.