Use lodash/get for all Field components

Official React-Admin components use `lodash/get` to retrieve property values from the source. This makes it possible to pass `recipient.identity` paths to fetch blank nodes.

https://github.com/marmelab/react-admin/blob/3.x/packages/ra-ui-materialui/src/field/TextField.tsx#L13

We should use this same library for all our "Field" components (a priori in the @semapps/field-components package).

Start by reviewing the @semapps/field-components package and the linked React-Admin TextField example to identify every Field component that retrieves source values. Update the Field components to support nested paths such as recipient.identity, then verify that all affected components resolve those paths consistently.

Written by the indexing model from the issue text.