Add JWT auth and sandbox start/stop support
- Add lib/generateJwt and make JWT_SECRET/COOKIE_SECRET required in env
- Include Authorization Bearer JWT when calling sandbox
create/start/stop/delete
- DB schema: add sandboxes.repo and started_at, include migrations and
snapshots
- Update lexicons/types (status description -> "RUNNING", response ref
-> actor profile)
- Frontend: add start/stop/delete API calls, profile atom, UI/hooks
updates, add lodash dep