Initial Rust API:
```rust
use odcs::{parse_yaml_file, validate};
let contract = parse_yaml_file("contract.odcs.yaml")?;
let report = validate(&contract);
assert!(report.is_valid());
```
Alternative object-oriented API:
```rust
use odcs::DataContract;
let contract = DataContract::from_yaml_file("contract.odcs.yaml")?;
let report = contract.validate();
```
Keep this API parallel to `dtcs` where practical.