Refactor data grid behavior into `useDataGrid()` hook

[craxal]

The purpose of this prototype is to:

• Establish a pattern of organizing state and reducers into a hierarchical structure. Hooks such as useDataGrid() that implement a complex set of behaviors can delegate state and behaviors to sub-hooks, which makes reasoning, debugging, and maintenance easier.
• Simplify the DataGrid component implementation by hoisting state and behaviors into a hook and leaving derivative work within the component.
• Factor out common explorer behaviors into components/hooks. For example, create a useDataSource() sub-hook to encapsulate properties and behaviors related to loading.

[craxal]

Pushing back due to higher-priority items.

[craxal]

In regard to the DataGrid component, this work is essentially done. Other points are tracked by other work items.