Feat: add indexes to columns

[kiwicopple]

Feature request

Is your feature request related to a problem? Please describe.

It would be great to be able to add an index to a column

Describe the solution you'd like

Perhaps a right-click > Add index > Sidebar / dialog?

Additional context

We need to consider a few more items:

• A user should be able to add a multi-index column somehow. docs
• A user should be able to choose the type of index: docs
• Eventually we need to support all of the functionality of Postgres indexes, but I think the lowest hanging fruit is just a single-column index where they can choose between B-tree, Hash, GiST, SP-GiST, GIN and BRIN