FINERACT-2657: Fix NPE updating a provisioning criteria by matching definitions on categoryId

[oluexpert99]

Description

• ProvisioningCriteria.update matched incoming definitions by the surrogate id, but the public UPDATE
  payload keys each definition only by categoryId, so data.getId() was null and update() threw a
  NullPointerException (HTTP 500) on every provisioning-criteria update.
• Match the existing definition by categoryId (its natural key, unique per criteria) and reject an
  unknown categoryId with a clean validation error instead of the NPE; add a getCategoryId() accessor
  on ProvisioningCriteriaDefinition.
• Add ProvisioningCriteriaTest covering the match-by-categoryId update path and the unknown-category
  validation path.

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