feat(testmanagement): add optional test_case_bdd field for BDD/Gherkin template support

[tadeorosochackinx]

Summary

Adds an optional test_case_bdd parameter to createTestCase and updateTestCase tools, enabling BDD/Gherkin template support.

Changes

• create-testcase.ts: Added test_case_bdd to interface, Zod schema, and function body
• update-testcase.ts: Same pattern

How it works

When test_case_bdd is provided (with feature, scenario, and optional background), the fields are flattened into the API body with template: "test_case_bdd". When omitted, behavior is 100% unchanged.

[idegterov]

Hit this gap in practice today: createTestCase/updateTestCase currently have no way to write native feature/background/scenario fields, so any BDD-template test case can only be updated via description/preconditions/test_case_steps — which either flattens Gherkin into a step list or gets rejected outright (test_case_steps on a test_case_bdd-template case returns an error from the backend).

Confirmed the underlying PATCH /api/v2/projects/{project}/test-cases/{identifier} endpoint already accepts feature/background/scenario directly when called outside this client (200, values persist) — so the backend fully supports what this PR adds, it's just not exposed here yet.

This has been open ~7 months and just went stale (CONFLICTING). Any chance of a rebase + merge? Happy to help test against a real BDD project if useful.

[idegterov]

Opened #392 to track the underlying problem this PR fixes, since I couldn't find an existing issue for it — just linking them together.