[META] Workflow editor

[ohltyler]

Introduce a workflow editor containing a drag-and-drop workspace where users can stitch together generic building blocks to build out their applications. When validated, they can launch their workflow to create any necessary resources and begin to prototype.

Proposed mock as of 2/19 from @opensearch-project/opensearch-ux:

• Read-only workspace #10
• Custom workflow workspace #20
• [Workflow editor] Fine-grained validation #5
• [Workflow editor] Add basic placeholder building blocks #73
• [Workflow editor] Add component library #74
• [Workflow editor] Integrate with backend APIs #75
• [Workflow editor] Support initial building blocks #82

[ohltyler]

Basic components and functionality complete. Drag-and-drop is deprioritized so removed that from this meta issue. Resolving.