Refacto: Improve CH code suggestions management.

[SarahBellaha]

Description

To improve the efficiency and accuracy of updating operational points and their suggestions, we need to refactor the current implementation. The following changes are proposed:

• Add availableSecondaryCodes in StdcmPathStep location.
• Update availableSecondaryCodes in StdcmOperationalPoint when changing the ci.
• Build chSuggestions from availableSecondaryCodes.
• Update availableSecondaryCodes when selecting an op in linked train:
  • This can be done either by using already available secondary codes or by fetching them with searchOperationalPoints.
• (Optional, if needed above): Refactor useSearchOperationalPoint hook:
  • Extract the state-setting logic from the searchOperationalPoints function.
  • Modify the function so that it returns its results and takes the query as an argument.

Acceptance Criteria:

• Add availableSecondaryCodes field to StdcmPathStep location.
• Update availableSecondaryCodes in StdcmOperationalPoint when ci changes.
• Ensure chSuggestions are built from availableSecondaryCodes.
• Update availableSecondaryCodes when an op is selected in linked trains.
• (Optional) Refactor useSearchOperationalPoint hook to return results and accept a query argument.