v3.4.4

Released 2026-07-12.

A capability release that adds the experimental MCP Tasks protocol surface to
the Bernstein MCP server, plus release-pipeline hardening.

MCP Tasks extension

• Long-running runs are now exposed through the experimental MCP Tasks protocol.
  A task-capable MCP client (Claude Code, Cursor, Cline, and others) can start a
  run with bernstein_run, receive a CreateTaskResult, and then poll status
  and retrieve the result asynchronously through the get_task,
  get_task_result, list_tasks, and cancel_task handlers without holding a
  blocking session open. The task handle embeds the run's audit-chain head hash
  ({task_id}:{head_hash}) so a stateless client can still tie a progress claim
  back to the signed chain.

• W3C trace-context (traceparent, tracestate, baggage) is ingested from
  the incoming request and propagated to the spawned agent, scoped per task so a
  run without trace-context never inherits another run's context.

• Every task status projects to a terminal MCP status on completion, and
  get_task_result reports an error for terminal-error and in-flight tasks
  instead of reporting success.

  Thanks to @Amanmeena0 for contributing the MCP Tasks protocol implementation
  and the trace-context propagation.

Release pipeline

• The MCP registry listing publish is now idempotent: a version that is already
  live is treated as success instead of failing the release on a re-run or a
  tag-push/dispatch race. (#2466)

Housekeeping

• Refreshed the packaged adapter last-green projection and its docs table from
  the nightly conformance canary; every row stays anchored to its attesting
  receipt.