addWeaveSpanAdapter

Installs the W&B Weave SpanAdapter without registering the Weave cloud exporter. Spans are reshaped to the Weave-recommended attribute layout but are emitted only through whatever exporters the caller registers separately.

Useful for tests that want to assert on Weave-shaped spans without performing a real HTTP round-trip and for integrators who want the Weave transformations applied to spans they ship to a different backend.