4499 add controller tests for high priority untested modules

[DeboraSerra]

Describe your changes

Six of the seven controllers named here already had passing suites, so this covers the real
gaps: a new advisor.ctrl.ts suite (73 tests; SSE streaming excluded) and branch top-ups on
fileManager and approvalRequest. On the frontend, existing error tests asserted against a bare thrown Error, so the MSW error scaffold now spans six domains with 25 tests using the real { message, data } envelope. Two findings for reviewers: the scaffold's envelope was inverted and is fixed here; getFileErrorMessage branches on statusCode while apiServices throws .status, so those branches are dead — pinned by tests, left unfixed as it changes user-facing copy.

Write your issue number after "Fixes "

Fixes #4499

Please ensure all items are checked off before requesting a review:

• I deployed the code locally.
• I have performed a self-review of my code.
• I have included the issue # in the PR.
• I have labelled the PR correctly.
• The issue I am working on is assigned to me.
• I have avoided using hardcoded values to ensure scalability and maintain consistency across the application.
• I have ensured that font sizes, color choices, and other UI elements are referenced from the theme.
• My pull request is focused and addresses a single, specific feature.
• If there are UI changes, I have attached a screenshot or video to this PR.
• If I added or modified an API endpoint, the change is reflected in the generated OpenAPI spec (npm run generate:swagger).
• If the endpoint requires authentication, it uses authenticateJWT and the generated spec declares bearerAuth security.
• I ran npm run check:api-drift and committed the regenerated swagger.yaml and endpoints.ts.
• If this PR adds or modifies an organization-scoped table, the tenant isolation registry and test matrix are updated. See the tenant isolation runbook for details.

[github-actions]

✅ Coverage Gate Passed

All coverage thresholds are met.

[MuhammadKhalilzadeh]

Thank you @DeboraSerra
Let's fix the failing github checks as well