Hackathon: update resource file validation to support the new resource data model

[rmadupuri]

• Updated the validator for resource data to support the hierarchical grouping model introduced in plan.md

Five optional columns were added to data_resource_patient.txt, data_resource_sample.txt and data_resource_study.txt:

• DISPLAY_NAME : human-readable label for the item in the UI tree
• TYPE : free-text badge label (e.g. H_AND_E, CT, BAM)
• GROUP_PATH : /-separated folder path defining the item's position
  in the resource tree (e.g. CT 2023-01-15/Series 1: Axial T2)
• METADATA : JSON string for domain-specific key/value data
• PRIORITY : integer display order within a folder or category

Validator changes

• Added optional headers to SampleResourceValidator, PatientResourceValidator and StudyResourceValidator
• Added PRIORITY and METADATA validation: PRIORITY must be a valid integer when present; METADATA must be valid JSON when present

Test changes

• Updated data_resource_sample_valid.txt, data_resource_patient_valid.txt,
  and data_resource_study_valid.txt with the new optional columns
• Added data_resource_patient_invalid_metadata.txt and data_resource_patient_invalid_priority.txt