NgSurvey integration

[Pa-Touche]

Summary

Introduces an end-to-end pipeline that lets an external survey tool (ngSurvey) push answer payloads back into SORMAS and have them turned into a CaseDataDto patch.

Feature is broken down into following layers:

• API layer (sormas-api): new DTOs/facades for external survey messages, a DataPatcher contract, a PartialRetriever contract, plus mapping/alias support.
• Backend (sormas-backend.patch) - an in-house mini-framework on top of Apache Commons PropertyUtils:
  • DataPatcherImpl orchestrates per-field patching with a result-collecting pipeline.
  • PartialRetrieverImpl reads back the same paths for display.
  • Pluggable ValuePatchMapper (date / enum / customizable enum / primitive / reference DTO) and FieldCustomMapper (person contact details, person birthdate) registries.
  • EqualityChecker registry used when DataReplacementStrategy.IF_NOT_ALREADY_PRESENT.
  • PathAliasHelper lets external systems address fields by their Field ID (see: SORMAS Data Dictionary) instead of the full DTO path (e.g. Symptoms.fever instead of CaseData.symptoms.fever).
• Survey integration (sormas-backend.externalmessage.survey) - AutomaticSurveyResponseProcessor consumes ExternalMessageDtos, resolves the SurveyToken, and feeds the DataPatcher.
• UI: new views/forms for survey/token management and survey-response details.

The core abstraction (path-based patcher with pluggable mappers, validators and aliases) is reusable beyond ngSurvey.

Fixes #13832