Add granular token authorization to MLOps types in GraphQL

What does this MR do and why?

• Every GraphQL type in the mlops feature category now declares authorize_granular_token.
• MlModel and MlExperiment are the only two exposed as root query fields, so they are the entry points a granular token must be scoped for. The others are children of those two and are gated by the parent's permission when the query traverses to them.
• No new permissions were needed. read_ml_model and read_ml_experiment already exist with project-boundary from REST

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