2.30.0

Added

• Harness engineering workflows for suite diagnostics, held-in/held-out evaluation,
  multiple candidate comparisons and project experiment history.
• Guided native decision tuning with saved experiments, labels and rationales,
  uncertainty selection, random audit samples and sealed-test evidence.
• Credential-free setup checks and offline synthetic tuning practice so developers
  can explore the workflow before configuring a model or paying for execution.

Fixed

• Reject candidate adoption based on incomplete, ungraded, smoke-only,
  contradictory or regressed held-out evidence. Accepted experiment candidates
  do not automatically overwrite or activate a project harness.
• Drain desktop background writers before database shutdown, reject new work
  while closing, and improve ACP, Codex and terminal subprocess cleanup.
• Update compatible Authlib, certificate trust, DNS and filesystem dependencies.

This is the Python publication of the harness changes prepared under 2.26.0,
alongside the macOS 0.2.0/build 14 Public Beta. Known dependency and lifecycle
findings remain documented in apps/macos/RELEASE-READINESS-0.1.12.md.