Adds the following attribute to
`sui_graphql_rpc::types::object::Object`:
```rust
    /// Optional root parent object version if this is a dynamic field.
    ///
    /// This enables consistent dynamic field reads in the case of chained dynamic object fields,
    /// e.g., `Parent -> DOF1 -> DOF2`. In such cases, the object versions may end up like
    /// `Parent >= DOF1, DOF2` but `DOF1 < DOF2`. Thus, database queries for dynamic fields must
    /// bound the object versions by the version of the root object of the tree.
    ///
    /// Essentially, lamport timestamps of objects are updated for all top-level mutable objects
    /// provided as inputs to a transaction as well as any mutated dynamic child objects. However,
    /// any dynamic child objects that were loaded but not actually mutated don't end up having
    /// their versions updated.
    root_version: Option<u64>,
```

I tried making sure that this attribute is set correctly wherever an
`Object` is created.

There's one scenario which still isn't covered: if the GQL query is
rooted at a DOF, something like
```graphql
query DynamicFields($parent: SuiAddress!, $version: Int, $after: String) {
  object(address: $parent, version: $version) {
    dynamicFields(/* ... */) {
        // ...
    }
  }
}
```
where `$parent` is a DOF's object id, then the server has no way to know
the root object's version. Instead, we will use the rooting object's version, even if it is a nested child object.

New tests `immutable_dof.move` and `nested_dof.move`.

---

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any actions they must take to implement updates.

- [ ] Protocol:
- [ ] Nodes (Validators and Full nodes):
- [ ] Indexer:
- [ ] JSON-RPC:
- [x] GraphQL:
- [ ] CLI:
- [ ] Rust SDK:

---------

Co-authored-by: Ashok Menon <amenon94@gmail.com>
Co-authored-by: Will Yang <willyang@mystenlabs.com>