Prepare `actions` to be a core feature agnostic package

[0xjei]

Description

This issue is related to a technical debt from the previous iteration performed to separate the phase2cli and actions packages in a way that makes core functionality shared between the packages and reusable to build interfaces/clients.

This part is also critical to facilitate and complete testing (e2e and unit).

This issue is focused on eliminating code repetitions, improve some methods making them agnostic (the ones already separated), libs specialization and separation will be improved, custom types and environment variables will be commented and documented, and error handling will be improved in accordance with the new guidelines.

_This work will be critical for the subsequent optimization part of the CLI and Cloud Functions commands in the backend.__

Note that

Todo

• [x] Make actions helpers and lib agnostic (actions package)
• [x] Optimize amount of code (quality, readability, remove duplications)
• [x] Move core types and constants to actions
• [x] Add custom methods to recreate paths
• [x] Avoid duplications between packages
• [x] Sync backend and phase2cli packages
• [x] Add missing documentation for environments #214
• [x] Add missing documentation for custom types #213

Affected issues

• 279

• 277

• 275