Don't show agents over quota in the Workspace agent dropdown

MR: Pending

Description

In #426512 (closed) we implemented limits on workspaces imposed at a per-agent level. By enforcing these limits, we put the user in a position to encounter errors during the creation of their workspace.

If the total number of workspaces currently running on an agent has reached the quota, or I have reached my per_user quota, I can't create a workspace on that agent.

It's important to note that I may have access to multiple agents, so we can't resolve this by preventing access to the New workspace view entirely.

Current experience

Validation doesn't occur until after the user tries to create a workspace, at which point we display an error.

Proposal A

Hide or otherwise prevent agents that can't accept new workspace from the current user from the dropdown in the UI.

Proposal B

Allow a user to select any properly configured agent, but perform the validation before the form has been submitted. Disable the button and display a clear error message that indicates why the user can't create one at this point.

Acceptance Criteria

• TBD

Design Requirements

Impact Assessment

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User Story

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