sources/spanner-omni: New spanner-omni source connector type — reads change streams from Spanner Omni with IsExperimentalHost: true, plain-text gRPC, no GCP auth. Registered alongside existing spanner type.
sinks/spanner-omni: New spanner-omni sink connector type — writes mutations to Spanner Omni using the same connection model. endpoint is a required field; credentials_file is omitted.
sinks/spanner + sources/spanner: Both existing spanner connectors gain IsExperimentalHost: true automatically when a custom endpoint is set, making them compatible with Spanner Omni and the Cloud Spanner emulator without a separate type.
testing: Cloud Spanner emulator (gcr.io/cloud-spanner-emulator/emulator) completely replaced by Spanner Omni (us-docker.pkg.dev/spanner-omni/images/spanner-omni:2026.r1-beta) across all integration tests, CI, and dev scripts.
testing: 27 new E2E integration tests for the SQLServer→Spanner Omni pipeline: 12 CUJ tests with real Spanner row verification, 8 CUJ suite tests (SS-SP-13..20) including Unicode NVARCHAR round-trip, auto-create-table, and idempotency, and 7 failure/recovery tests (SS-SP-21..27) mirroring the SQLServer→Redpanda failure suite.
helpers:StartSpannerOmni(t, ctx) testcontainer helper with ApplyDDL, NewSpannerClient, and SpannerOmniSinkProps methods — replaces StartSpannerEmulator.
scripts:setup-spanner-dev.sh rewritten for Spanner Omni single-server mode (port 15000, project/instance auto-discovered via CLI).