CI: Integration Tests job fails on main (live gateway tests run with no gateway / no base URL)

[njbrake]

Note: this issue was drafted by Claude via back-and-forth with @njbrake. The reasoning and decisions are his; the prose is Claude's.

The CI workflow's Integration Tests job has been failing on main on every push for a while (at least since 2026-04-28, well before the Option C SDK migration). It is unrelated to the SDK code: the Test, Clippy, Format, Docs, MSRV, and Check jobs all pass.

Cause

tests/integration_batch.rs contains #[ignore = "requires a running gateway server"] live tests (live_create_and_retrieve_batch, live_retrieve_batch_results_not_complete). The CI job runs them via --ignored, but GitHub CI has no gateway, and the tests build a client from Config::default() (no base URL), so the first request panics:

called `Result::unwrap()` on an `Err`: Http(reqwest::Error { kind: Builder, source: RelativeUrlWithoutBase })

So the job can never pass in CI as written, because it executes live gateway tests with no gateway and no base URL configured.

Suggested fix (pick one)

• Skip when unconfigured (preferred, matches the Python and Go SDK integration tests): have each live test early-return/skip when the gateway base URL env var is absent, instead of constructing a client with an empty base. This keeps main green while still letting the tests run locally against a real gateway.
• Or gate the Integration Tests CI job so it only runs when a gateway is provisioned (for example a service container or an explicit OTARI_GATEWAY_* env), rather than on every push.

Notes

Found while merging the Option C SDK migration (#27). The migration itself is green on all other jobs; this is a separate, pre-existing CI issue and should not be attributed to that work.