#254: Add unit tests for dictionary data file templates

[Azher2Ali]

#254 : Add unit tests for dictionary data file templates

Summary

Added unit tests to validate the creation of dictionary data file templates, ensuring correct headers, delimiters, placeholder lines, and filenames are generated according to the schema and configuration.

Issues

• #218: add endpoint to download TSV template files for all data entities #252

Description of Changes

Server

Added unit tests for createDataFileTemplates method

• Verifies that every header defined in the schema is added to the template
• Confirms headers are added in the correct order as specified by the schema
• Asserts that an empty row is created with one placeholder value for each header
• Checks that the configured delimiter is applied correctly:
  • for custom-specified delimiters
  • for known file types (e.g. .tsv, .csv)
• Validates that the generated template filename:
  • matches the schema name plus the configured file type
  • uses the correct file extension based on the configuration and known file types

Special Instructions

Before running these changes, you will need to ...
pnpm install
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Readiness Checklist

• Self Review
  • I have performed a self review of code
  • I have run the application locally and manually tested the feature
  • I have checked all updates to correct typos and misspellings
• Formatting
  • Code follows the project style guide
  • Autmated code formatters (ie. Prettier) have been run
• Local Testing
  • Successfully built all packages locally
  • Successfully ran all test suites, all unit and integration tests pass
• Updated Tests
  • Unit and integration tests have been added that describe the bug that was fixed or the features that were added