[CWL Executor] Refactor ProductionHint to work with existing plugin system

This `InputDatasetPluginRegistry` is very similar to the existing `ExecutionHooksPluginRegistry` (https://github.com/ryuwd/dirac-cwl-proto/blob/5b22fe6c10ac348a8ca0ecacf19d3242c2bacf31/src/dirac_cwl/execution_hooks/registry.py). I know you don't want to interfere too much with the current implementation, but your proposal looks reasonable and interesting to me, and therefore, I wonder if both could not be refactored. Any opinion?

I know you are also in a rush, so if you agree and don't think you will have time to connect them easily, then please open an issue as a reminder. Thanks 🙂

_Originally posted by @aldbr in https://github.com/DIRACGrid/dirac-cwl/pull/94#discussion_r2774274087_