Feature: `workspace_contributor_insights` join table

[jpmcb]

Type of feature

🍕 Feature

Current behavior

Currently, workspaces do not have / are not associated with user lists (now being called contributor insights): they are only associated to a single user via the user_id

Suggested solution

Let's make workspaces associated to users via a workspace:

This likely will require work in #510 to be done so personal workspaces can have their associated user lists for current users

Additional context

No response

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