fix(activation): a pending receipt gates dispatch, not reads; preflight consumes the nonce; deliver identity not the body

[thewrz]

This was written agentically; verify its assertions:

Tracking issue for the activation-gate Option B plan (branch fix/activation-option-b).

A parallel-issues root paid six tool calls of activation ceremony before its first real call on 2026-09-23: two denied reads, an ack, two checks, one preflight. The hook also shipped the 66 KB skill body as context that both harnesses truncated and spilled to disk while the native skill injection delivered it in full. The receipt is still the only proof against the #722 class (six hours, 261.8M tokens with no plugin loaded), so it stays; the ceremony goes.

• A pending receipt gates dispatch-class calls only (spawn, worktree creation, push, PR creation). Reads, edits and inspection proceed.
• agent-preflight.sh --activation-nonce promotes the receipt inside the first call every workflow already makes; a wrong nonce fails before any state is written.
• Delivery is the preflight line plus workflow identity, under 1,500 characters; SessionStart re-delivery is the same shape.
• bench/activation-ordering.sh proves on both harnesses that hook context arrives before the model's first tool call.

🤖 Co-authored by Claude Fable 5.1 (noreply@anthropic.com)

🤖 Generated with Claude Code

[thewrz]

This was written agentically; verify its assertions:

Duplicate of #893, which is the tracking issue for this work and is what PR #894 closes. Filed by mistake by an implementation worker during the sprint.

🤖 Co-authored by Claude Fable 5.1