fix(auxiliary): _wrap_if_needed uses the effective (post-override) base_url in the API-key branch

[ygd58]

Fixes #85535.

Root cause

In the generic API-key branch of resolve_provider_client(), when a fallback entry carries an explicit_base_url override, the actual OpenAI client is built with the override (base_url) -- but the final _wrap_if_needed() call still passed raw_base_url, the pre-rewrite value, not the effective URL the client was actually constructed with. Every other _wrap_if_needed call site was already guarded against this class of bug (#85466, #85532, plus three older PRs); this was the one residual, uncovered site.

Fix

Pass base_url (already holding the correct, override-aware, effective URL) instead of raw_base_url.

Verification

Used a real repro: an explicit_base_url override to api.kimi.com/coding, rewritten to api.kimi.com/coding/v1 for the OpenAI client. Both forms match the Anthropic-wrap heuristic, so whether the wrap happens doesn't distinguish the bug -- but the exact URL string passed to build_anthropic_client does. Before the fix it received the stale, /v1-less URL, inconsistent with the endpoint the underlying OpenAI client actually used.

Added a regression test extending the existing test file. Verified as a genuine regression by reverting the fix and confirming the test fails with the exact stale, inconsistent URL.

191/191 pass across four directly related test files (no regression).

[Enough1122]

AI code review — automated review for reference, author can ignore or act on any point.

fix(auxiliary): _wrap_if_needed uses the effective (post-override) base_url in the API-key branch

No blocking issues found. This is a correct, minimal one-line fix with a strong regression test (asserts the exact URL the Anthropic client is built against, not just the wrap decision).

Minor observations:

1. Sibling branch may share the stale-value hazard. The test comment notes the /anthropic-suffix branch is entangled with the separate fix(auxiliary): only rewrite /anthropic to /v1 for dual-surface hosts (salvage #83782) #85532 rewrite-policy fix. Confirm that follow-up covers the sibling branch so the wrap decision there cannot diverge from the actual client endpoint the same way this PR fixes here.

2. raw_base_url may now be a trap. If raw_base_url is only referenced by this now-fixed branch, consider removing it (or renaming to make "pre-rewrite" explicit) so a future edit can't accidentally reintroduce the mismatch; if it is still used elsewhere, a brief comment at its definition would help.