Adopt delivery ledger for pi and OMP

[schickling-assistant]

Summary

• adopt the transactional delivery ledger for pi and OMP
• durably claim before sendUserMessage and prepend the canonical attempt marker
• treat transport return/throw as ambiguous; settle only from archive receipts or exact operator absence
• exclude declaration-root ledger state from catalog projections

Part of #506. Depends on #515.

Verification

• nix build .#checks.x86_64-linux.st2 --no-link --print-out-paths --print-build-logs --max-jobs 1 --cores 2
• nix build .#checks.x86_64-linux.pi-extension-types
• named pi/OMP transactional and restart-safety invariant tests
• delivery-negative CLI, catalog projection, and retired-roster regressions
• real OMP 18.1.7 production-wrapper probe
• real Pi 0.84.4 production-wrapper probe with the repository deterministic model server

Review

• independent focused review completed; all findings fixed and re-reviewed clean
• overlaps draft feat: compose clean agent lifecycle states #513 in shared delivery files; this PR is the Make native delivery claims transactional across all harnesses #506 stacked adoption path

Posted on behalf of @schickling

field	value
agent_identity	dev3.direct.omp.9exwnk6h
session	dev3.9exwnk6h
agent_persona	generalist
agent_supervisor	unavailable
agent_tool	OMP
agent_tool_version	18.1.7
agent_runtime	OMP 18.1.7
tooling_profile	dotfiles@931583a