Address the ds-review-bot v5/v6 review on PR #3849:
- Register the shared `lib/json-stream-*.js` chunk in `packageFileExtras` and
order `files` as the workspace-constraints gate requires, so
`pnpm run constraints` passes.
- Re-validate the preset on the Session `agents.resume` actually attached,
closing the TOCTOU window between `observeSession` and the write lease.
- Bound one serialized event line at 32 KiB: an over-long event keeps its
scalar fields, drops structured ones, and at the extreme reduces to `type`.
- Normalize an empty tool-argument string to `{}`, matching the executor.
- Scan only real `--json` flags (stop at `--`, skip a `--session-id` value)
before installing the JSON error override.
Tests: 74 headless unit tests with per-file 100% coverage on src, 14 profile
e2e tests, constraints/typecheck/lint/doc/pairing gates, tarball import smoke.