Other costs accept array

[Kariamos]

This pull request updates the PATCH endpoint for /campaigns/:campaignId/finance/otherCosts to support bulk updates of multiple cost items in a single request. The OpenAPI documentation and test suite have been updated to reflect and validate the new array-based request and response structure. Validation and error handling are now performed per item, with improved error messages for batch operations.

Bulk Update Support and Validation Improvements:

• The PATCH endpoint now expects and returns an array of cost items, enabling bulk updates in a single request. The OpenAPI schema and example payloads have been updated accordingly. [1] [2] [3] [4] [5] [6]
• Validation logic has been enhanced to check that the request body is a non-empty array, and to validate each item individually, returning specific error messages that indicate the index of the invalid item (e.g., "Item 1: cost_id must be a positive number"). [1] [2] [3] [4] [5] [6] [7] [8] [9] [10]

Test Suite Updates:

• The test payloads have been refactored to use arrays, and new tests have been added to cover scenarios such as sending a non-array body, empty arrays, and updating multiple costs in a single request. [1] [2] [3]
• Tests now verify that the response is an array of updated items, and that error messages are specific to the item index in batch operations. [1] [2] [3] [4] [5]

These changes ensure the API is more flexible and robust for clients needing to update multiple cost items at once, with clearer feedback on any validation issues.

[github-actions]

Tests difference:

New Tests

< Input Validation - Should return 400 if array is empty
< Input Validation - Should return 400 if body is not an array
< Success - admin permissions - Should create multiple costs in single request
< Success - admin permissions - Should update multiple costs in single request
< Validation errors - Should return 400 for second item with invalid data
< Validation errors - Should return 400 if body is an empty array
< Validation errors - Should return 400 if body is not an array