chore(1.85): 1.85.0 readiness (#2937)

see passing action here:
https://github.com/FuelLabs/fuels-rs/actions/runs/14362772711/job/40268264149?pr=1639



This pull request includes several updates to the `Cargo.toml` file and
modifications to the `OffChainIterableKeyValueView` implementation in
the `graphql_api` adapter. The most important changes are summarized
below:

### Dependency Updates:
* Added `serde_with` as an optional workspace dependency in
`Cargo.toml`.
* Updated the default features to include `serde` and added a new
feature `serde` that depends on `serde_with` in `Cargo.toml`.

### Code Enhancements:
* Changed the lifetime annotation for return type in three methods of
`OffChainIterableKeyValueView` from `BoxedIter<'_, Result<(AssetId,
u128), StorageError>>` to `BoxedIter<'a, Result<(AssetId, u128),
StorageError>>` to ensure consistency in the `graphql_api` adapter.
[[1]](diffhunk://#diff-a2c13bbe4fe3673e734fec61faaa1cf60dbd59a45b6567cd13f596b36e090f6cL336-R336)
[[2]](diffhunk://#diff-a2c13bbe4fe3673e734fec61faaa1cf60dbd59a45b6567cd13f596b36e090f6cL367-R367)
[[3]](diffhunk://#diff-a2c13bbe4fe3673e734fec61faaa1cf60dbd59a45b6567cd13f596b36e090f6cL382-R382)