Add GET /bills/:id endpoint with Bill type aligned to bills.json schema

[Copilot]

• Remove BillFailureReason enum, change failureReason to string
• Strengthen bills endpoint test
• Fix lint errors in BillPaymentMethod
• Remove | null from paymentMethod?: BillPaymentMethod | null → paymentMethod?: BillPaymentMethod

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[Copilot]

Pull request overview

This pull request adds support for retrieving bill resources via the /bills/:id endpoint in the Unit Node SDK. The implementation follows established patterns in the codebase for simple resource classes with get methods, similar to Institutions and Disputes resources.

Changes:

• New Bill type definition with status union type and comprehensive attributes/relationships
• New Bills resource class with a single get(id) method
• Integration with the main Unit class to expose the bills resource
• Test coverage for both type validation and the get endpoint

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
types/bill.ts	Defines the Bill interface with BillStatus union type, standard attributes (createdAt, status, amount, description, reason, tags), and relationships (account, customer, customers, transaction)
resources/bills.ts	Implements Bills resource class extending BaseResource with a get method to retrieve a bill by ID
unit.ts	Adds Bills resource to the Unit class constructor and public properties
types/index.ts	Exports bill types for external consumption
resources/index.ts	Exports Bills resource class for external consumption
tests/bills.spec.ts	Adds tests for Bill type structure and get endpoint functionality

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[hassidtal]

@copilot look at the attributes and statuses, the types/bill.ts is not align with https://github.com/unit-finance/unit-finance/blob/master/Unit.Api/schemas/public/bills.json

[Copilot]

@copilot look at the attributes and statuses, the types/bill.ts is not align with https://github.com/unit-finance/unit-finance/blob/master/Unit.Api/schemas/public/bills.json

The unit-finance/unit-finance repository is private and not accessible to me, so I'm unable to read the bills.json schema directly. Could you share the relevant schema content (or a diff of what needs to change) so I can align the attributes and statuses correctly?

[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

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[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.

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[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

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[Copilot]

The paymentMethod field is marked as both optional (?) and nullable (| null). In TypeScript, optional properties can already be undefined, so adding | null means this field can be undefined, null, or a BillPaymentMethod value.

This pattern is inconsistent with other readonly resource types in the codebase (e.g., Dispute, Fee) which use only ? for optional fields. The | null pattern is primarily used in update request types where null has a specific semantic meaning (to delete a field).

If the API can return an explicit null value for this field (as opposed to omitting it entirely), then this typing is correct. However, if the field is simply absent when no payment method exists, consider removing | null to be consistent with other resource types.

Suggested change

	paymentMethod?: BillPaymentMethod | null
	paymentMethod?: BillPaymentMethod

[hassidtal]

@copilot fix

[Copilot]

Fixed in ea4b183 — changed paymentMethod?: BillPaymentMethod | null to paymentMethod?: BillPaymentMethod.

[YegorZh]

lgtm