Update resolvedData docs for relationships - take 2 (#6665)

docs/pages/docs/apis/hooks.mdx

@@ -432,10 +432,12 @@ The data resolving steps are applied in the following order:
 
 1. Initialisation: Set the value of `resolvedData` to the `data` input value from the GraphQL mutation.
 2. Defaults (built in, `create` only): Any fields which have a default value and are `undefined` in `resolvedData` will be set to their default value.
-3. Relationships (built in): The values for relationship fields on `resolvedData` are either an ID string (for `one` relationships), or an array of ID strings (for `many` relationships).
+3. Relationships (built in): The values for relationship fields on `resolvedData` are [Prisma nested write objects](https://www.prisma.io/docs/concepts/components/prisma-client/relation-queries/#connect-an-existing-record).
    This is the format expected when saving relationship fields to the database.
-   The value is computed by combining the provided `connect`, `create`, `disconnect`, and `disconnectAll` values with the existing data in the database.
-   Any nested create operations are performed as part of this process.
+   Any nested create operations are performed during this phase. Their IDs are returned, and combined with any `connect` inputs.
+   All items provided for `connect`, `set`, and `disconnect` are checked to ensure they exist.
+   For to-many relationships, an object with the shape `{ connect: [...], set: [...], disconnect: [...] }` is returned.
+   For to-one relationships, an object with the shape `{ connect }` or `{ disconnect: true }` is returned.
 4. Field values (built in): Some fields types take the value given in the GraphQL operation and convert it into a different type or format to be saved to the database.
 5. Field hooks (user defined): A `resolveInput` field hook can return a new value for its field, which will the current field value on `resolvedData`.
 6. List hooks (user defined): A `resolveInput` list hook can return a new value for the entire `resolvedData` object.