Agentflow v8.4.5

Agentflow v8.4.5 adds the optional away-gates: on|off project setting. When enabled, it supplies Design Go and Result Go after the required evidence passes. Owner-only choices, Stop decisions, and failed checks remain in place.

The release also publishes the updated assistant brief at skills/agentflow/docs/agent-brief.md and links it from both public READMEs. The release tooling copies its exact committed bytes and refuses a missing source brief before changing the public checkout.

Release tests passed (16 development cases and 2 public cases). The public package was assembled from a clean source commit, checked for version and brief-byte equality, and passed independent review after a changelog correction.