Add user-configurable fields

[lmossman]

Context

In order to allow users to make their connectors built with the Connector Builder reusable, they need to have a place to specify user input fields, which they can then reference in other inputs in the UI.

The designs for this can be found in Figma here.

This UI will be used to build out the spec block of the connector manifest, which is then consumed by the Test inputs menu to render fields for users to fill out.

Acceptance Criteria

• User Input view select button exists in the sidebar
• User Input view has a button to add a new input, which opens a modal allowing them to configure the type and other metadata about the field, along with a preview of what the rendered input will look like
• The fields in the User Input view can be reordered to determine the order in the Test Inputs screen
• All other input fields have an embedded button which lets them select a user input field to use, adding the {{config['<field-name>']}} interpolated string value to the input upon selection

[flash1293]

Currently in progress

[flash1293]

Approved and merged into integration branch, waiting for the code freeze

[flash1293]

Merged