[adamtheturtle]

The shared VuMark suite and target-list rate-limit test still use the production VWS URL. Pass base_vws_url through both VuMark helpers and every caller, configure the locally created VWS client with it, and use the fixture in the rate-limit request.

This lets the existing SDK and raw-request assertions run against a service address supplied by another repository. Part of #3738 and #3737. It is independent of the unmatched-request adapter work in #3753.

Validation:

• Python 3.15: all 52 VuMark and rate-limit cases pass at the default URLs, with 24 real-backend cases skipped, synthetic credentials, and retries disabled.
• A separate consumer harness loads the same test functions and existing adapters, overrides the VWS/query URLs to loopback HTTP addresses, and passes the same 52 cases with 24 skips across both mock implementations.
• The complete VuMark directory has 100% local statement and branch coverage. The rate-limit test has 100% statement coverage; its only uncovered branch is the existing real-Vuforia case.
• Pre-commit and pre-push hooks pass, including CI partition validation, Mypy, Pyright, public type completeness, Ty, Pyrefly, and check-manifest. Pylint passes on all five changed files; git diff --check passes.

This changes five test files, with no source package, dependency, workflow, or coverage gate changes. Hosted full-suite validation will run on this PR.