test: add unit tests for invoice and user repositories

[CKodidela]

Description

Adds unit test specs for InvoiceRepository and UserRepository, covering all public methods with a stubbed DB client (no real database connections). Also fixes a pre-existing Windows incompatibility in the test:unit npm script where single-quoted globs were passed literally to cmd.exe.

New files:

• test/unit/repositories/invoice-repository.spec.ts (15 tests)
• test/unit/repositories/user-repository.spec.ts (16 tests)

Modified files:

• .mocharc.js moved spec glob here so mocha handles expansion cross-platform
• package.json simplified test:unit script to just mocha

Related Issue

Closes #491

Motivation and Context

These data-access layer components had virtually no test coverage. Poor branch coverage meant conditional paths (found/not-found, error propagation, vanish-state fallback) were completely untested.

How Has This Been Tested?

All tests use sinon sandboxes and a stubbed DatabaseClient — no real Postgres connection required.

Coverage after this PR (measured with nyc):

File	Statements	Branches
invoice-repository.ts	88% (was 21%)	100% (was 0%)
user-repository.ts	91% (was 21%)	100% (was 0%)

Full suite: 875 passing, 0 failing (npm run test:unit).

Types of changes

• Non-functional change (docs, style, minor refactor)

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my code changes.
• I added a changeset, or this is docs-only and I added an empty changeset.
• All new and existing tests passed.

[coveralls]

coverage: 74.014% (+0.9%) from 73.153% — CKodidela:test/invoice-and-user-repositories into cameri:main

[Copilot]

Pull request overview

This PR improves unit test coverage for the data-access layer by adding repository specs for InvoiceRepository and UserRepository, and updates the unit test runner configuration to be Windows-compatible by moving the spec glob into Mocha’s config.

Changes:

• Add unit tests for InvoiceRepository and UserRepository using stubbed DB clients (no real DB connections).
• Move the Mocha spec glob to .mocharc.js and simplify npm run test:unit to mocha for cross-platform compatibility.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
test/unit/repositories/invoice-repository.spec.ts	Adds unit tests covering InvoiceRepository public methods and mapping behavior.
test/unit/repositories/user-repository.spec.ts	Adds unit tests covering UserRepository public methods and vanish/balance/admission paths.
package.json	Simplifies test:unit script to rely on Mocha config for spec discovery (Windows fix).
.mocharc.js	Adds spec glob so Mocha handles test file expansion consistently across shells/OSes.

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[Copilot]

The test deletes invoice.id via delete (invoice as any).id, which bypasses the Invoice type (where id is required) to reach a code path. If UUID generation is intended public behavior, consider making id optional in the input type/signature; otherwise, prefer a dedicated input type or explicit cast at the call site rather than mutating a typed object.

[Copilot]

IUserRepository is imported but never used. This will typically fail lint/CI due to unused imports; remove it or use it for the repository variable type if that was the intent.

[Copilot]

makeDBInvoice uses null as any for nullable-looking DB fields (amount_paid, confirmed_at, expires_at). This weakens type-safety and likely means DBInvoice should model these as nullable (e.g., bigint | null, Date | null) so the test data can avoid any casts.