[adamtheturtle]

Complete the remaining shared query URL wiring in one change. Query request helpers and every caller now receive base_vwq_url; direct query requests, bad-key clients, configurable failure-response tests, and the remaining endpoint classifiers use the same fixture. Backend setup configures both MockVWS and the Flask adapters with the supplied service URLs, including the VWS URL needed by query setup and locally constructed VWS clients.

This advances #3738, part of #3737. It is independent of the invalid-JSON changes in #3749, which was awaiting auto-merge when this work started. The remaining production query URL literals represent the central default, deliberate default-URL regression inputs, an asserted Vuforia error-page body, or the real-service timeout policy.

Validation:

• Python 3.15: 271 query, bad-key, unexpected-body, payload, failure-response, and Flask application cases pass at the default URLs, with 98 expected skips.
• A separate consumer harness loads the existing shared tests and both existing backend adapters, overrides the VWS/query URLs to http://127.0.0.1:5006 and http://127.0.0.1:5007, and passes 230 cases with 118 expected skips. It reuses the existing assertions and adapter setup, so it verifies the URL overrides through both mock implementations.
• Fourteen of the sixteen changed files have 100% local coverage. Remaining coverage is in backend setup/control fixtures and existing real-only paths; full-suite coverage and real-Vuforia verification remain for hosted CI.
• Pre-commit hooks, CI partition validation, Mypy, Pyright, public type completeness, Ty, and Pyrefly pass. Pylint passes for every changed file, and git diff --check passes.

Both local test runs use synthetic credentials and disable pytest retries.