[ENHANCEMENT] Rename DevDesk to ZapDesk

## Summary
Rebrand the project from DevDesk to ZapDesk.

## Tasks

- [ ] Update code references from `devdesk` to `zapdesk`
- [ ] Update the local folder from `devdesk` to `zapdesk`
- [ ] Rename the GitHub repo from `devdesk` to `zapdesk`
- [ ] Change the logo from a "D" to a zap (see logo in the zendesk-zapdesk repo)
- [ ] Update any text that refers to DevDesk to ZapDesk