* Add secrets to the sidebar
* Get and put secrets (naive)
* Secrets list - shortcut
* Validates secret name
* Livebook secrets as environment variables
* Restores secrets when necessary
* Minor adjustments
* Implements add_system_envs for NoopRuntime
* Moves secrets to session data
* Granular operations for secrets
* Minor adjustments
* Applying suggestions
* Test for add secrets
* Type for secret
* Applying suggestions
* Prevents duplicates
* Refactor to live_render
* Update lib/livebook/session/data.ex
Co-authored-by: Jonatan Kłosko <jonatanklosko@gmail.com>
* Sort secrets
* Applying suggestions
Co-authored-by: Jonatan Kłosko <jonatanklosko@gmail.com>