Drop redundant getOperation() overrides in the AuthorizationIntent records

`AuthorizationIntent` exposes the operation through `getOperation()`. All seven implementations are records with an `operation` component, so their generated accessor is `operation()` — which means every record has to add a `getOperation()` override that just forwards to it.

The neighboring records already use canonical accessors (`AuthorizationRequest.principal()`/`intents()`, `ResolvedIntent.targets()`/`secondaries()`), so `getOperation()` is the only bean-style getter left in this area.

Renaming `getOperation()` to `operation()` lets each record's generated accessor implement the interface directly, so all seven overrides can go away. Pure rename, no behavior change.

Search for the seven AuthorizationIntent record implementations and their getOperation() overrides, then compare them with AuthorizationRequest and ResolvedIntent canonical accessors. Rename the interface method to operation() and remove the redundant overrides; done means all seven records use their generated accessors with no behavior change.

Written by the indexing model from the issue text.