[Part 1 / Phase 5] PathogenTestForm: Remove bridge methods and update section lifecycle

[roldy]

Problem Description

Context

Part of Epic: [Epic] PathogenTestForm: Composition + Stable Form Refactor
Blocked by: Phases 3 & 4

Clean up PathogenTestForm now that all sections are self-contained. Remove bridge methods,
instance vars that leaked into sections, and update swapDiseaseSection() to use the
rebuildSectionFieldAllowances() pattern.

Proposed Solution

Tasks

• Remove bridge methods: addSectionField, addSectionTubeFields, addSectionDrugSusceptibilityField, removeSectionField, getCurrentDisease
• Delete updateDrugSusceptibilityFieldSpecifications() — logic now lives in sections
• Remove drugSusceptibilityField and genoTypingCB instance vars
• Update swapDiseaseSection():
  • Call removeFromAllowedLists(oldIds) before unbind
  • Call rebuildSectionFieldAllowances(newIds) after bind
• Add rebuildSectionFieldAllowances(Collection<String> fieldIds) private helper
• Add removeFromAllowedLists(Collection<String> fieldIds) private helper
• Add section-type guard for IGRA tube setVisibleClear calls in testTypeField listener
• Replace updateDrugSusceptibilityFieldSpecifications() call with activeSection.onTestTypeChanged(...)
• Move remaining disease-specific fields (serogroup, serotype, genotype) out of common HTML_LAYOUT

Additional Information

Acceptance Criteria

• PathogenTestForm has no addSectionField, removeSectionField, getCurrentDisease, or updateDrugSusceptibilityFieldSpecifications methods
• swapDiseaseSection() compiles with new helpers
• mvn compile -pl sormas-ui passes