We have a new name

Herdr UI is now Sheprd.

Same app, new name, and a new home at sheprd.org.

• Your install keeps working. The in-app updater follows the rename, and your settings stay where they are.
• Your sessions are untouched. Terminals and agents keep running through the rename.
• The code moved too. It now lives at github.com/sheprd-labs/sheprd.