Add portable agent bootstrap sources and freshness checks

[iperev]

Summary

• Add portable integration source and read-only integration check routes for repository-local Codex and Claude skills. One bounded bootstrap delegates to the existing CLI owners; it does not copy workflow policy, install dependencies, or grant tool permissions.
• Bind freshness to the exact generated bytes and consumed invocation contracts. Confined observations preserve every traversed component and terminal position, so parent replacement, changed absence, and unsafe-kind changes cannot masquerade as a stable file.
• Extend descriptor, help, shipped contract, native witness, and installed npm/Python carrier coverage. Preserve the immutable 0.9.0 ABI fixture and its mutation controls while adding the compatible 0.10.0 edge.

Validation

Final candidate: 50bbd4663b8aed02dec3c0aebf344164adcff42f.
Reviewed tree: ec1295fdfacf172cfc205b727d38d5edf1745231.
Base: 6b4666ff70a4cca4d89b953cf2d11344f50a0624.

• Full npm run check passed on the final committed candidate, including 93 browser cases, package artifacts, installed carriers, self-hosting evidence, and release closeout.
• Focused native and race tests passed for integration, root-path confinement, and transaction inspection.
• Native Linux arm64 Docker tests passed for the same production owners; no emulation was used. The subsequent final delta changes only the opaque-observation JSON test envelope and passed its focused tests and static analysis.
• Independent portability/CLI, filesystem/state-machine, and ABI/evidence reviews completed with no remaining confirmed findings in their assigned scope. Eight isolated route-observation mutants and the bootstrap body-budget mutant were rejected by their intended assertions.
• git diff --check origin/main...HEAD passed; the worktree and final tree were unchanged after the full gate.

Boundaries And Follow-up

This slice generates and checks bootstrap files only. Installation, update, and removal remain explicitly open as INTEGRATION-01. A current result means generated-byte freshness, not host discovery, skill activation, ownership authentication, or authorization to overwrite a file. Native Codex/Claude host loading has not been proven. Local self-hosting receipts remain advisory; registry publication and provider evidence require the subsequent release workflow.

Retrospective

The corrective pass showed that equal leaf identity and bytes do not imply an unchanged traversal. The correction keeps the complete observation with its existing confined owner and independently tests each equality operand. Cheap static analysis now precedes another expensive final-gate attempt after test edits. No installed skills or consumer repositories were modified.

[iperev]

A read-only preparation pass for managed integration lifecycle reproduced a pre-existing internal transaction-plan boundary gap, tracked with a counterexample and scope in #102. The affected implementation is unchanged by this PR, and no production CLI route from re-admitted output to Apply was found. #102 is a required prerequisite before extending transactions with deletion; it is not counted as closed by this generation/check slice.