Beam 3.0.0 - Milestone 1

Milestone 1: No-Code and ML Focus.
Proposed Beam version reaches 2.70.0
Themes: Core improvements, API refinements, and groundwork for key features.

Deliverables:
Prism as the default local runner for all Python workflows
Deprecate ZetaSQL
Default option changes for IO connectors (e.g., BigQuery IO), Runners (e.g., SA vs SE)
Enrich YAML supports for IOs, turnkey transforms
Enrich Managed IO by onboarding more IOs and making Iceberg feature complete
ML features for RAG, Anomaly Detection
Consider reducing dependencies in core, moving more to separate/extra packages.

see https://s.apache.org/beam3-milestones