Implement ensure process ready

[iLLiCiTiT]

Description

Implement functionality that makes sure everything is set up for certain processes.

At this moment all the preparation happens during Tray initialization and startup, e.g. login. But when webactions will be used, there is no option to run or validate that preparations, because tray is not running, or is running in different process.

Webactions, especially those who require publishing, will ask ayon-core to ask all addons to prepare and validate their requirements. That part has to be implemented for shotgrid.

How would you imagine the implementation of the feature?

Implementation definition in ayon-core is here ynput/ayon-core#781 . Addon has to override ensure_is_process_ready where should happen whatever it needs to do. The method will receive ProcessContext where are metadata information about the started project, e.g. project name (does not have to be filled - e.g. traypublisher), if is in headless mode, which addon and version triggered the preparation.