Delete projects deactivated over retention period

[sahibamittal]

Current Behavior

Inactive projects which are no longer in use are retained in DT and take up unnecessary space in DB.

Proposed Behavior

Create a scheduled task to monitor the inactive projects.
If a project is deactivated for longer than the retention period, delete it.
Retention period can be set as env variable and can be modified in UI under administration.

Checklist

• I have read and understand the contributing guidelines
• I have checked the existing issues for whether this enhancement was already requested

[sahibamittal]

TBD: Should we keep at least 2 versions of projects irrespective of their status (active/inactive)?
@nscuro @VithikaS

[nscuro]

What's the use case for keeping projects despite them being inactive and eligible for deletion as per retention policy?

[sahibamittal]

Per discussion so far, retention policy should be based on either of two options below :

1. Age : Delete inactive projects if they're older than retention period of time.
2. Cadence : Keep 'x' number of inactive versions and delete the rest.

User can select either one of them and configure accordingly.

[sahibamittal]

1. Switch boolean project.active flag to inactiveSince timestamp -> DONE
2. Introduce retention policy that wipes projects inactive for >= 30 days per default
3. Make retention policy configurable (via UI)
4. Allow keep last X inactive versions “escape valve”
   1. “last X versions” is also based on inactiveSince, since we can’t reliably determine this by comparing version strings
   2. “last X versions” are kept despite being outside the retention duration

[sahibamittal]

Depends on #1641