test: cover missed regression suites in npm test

[ivansong1981]

Summary

• add five missed pure-JS regression suites to npm test
• bring memory-reflection.test.mjs back in line with the current sessionStrategy=none default
• let CI cover the previously unexecuted regression surface without changing runtime code

Validation

• npm test

[ivansong1981]

Checked the failing workflows locally and via GitHub Actions logs.

The code checks are green on this PR (version-sync and cli-smoke both passed). The failing checks are repo automation workflows, not the change itself:

• assign-prs: 403 Resource not accessible by integration when trying to assign the PR
• claude-review: unable to fetch OIDC token / ACTIONS_ID_TOKEN_REQUEST_URL missing, then Bad credentials

This looks like the usual fork-PR permission restriction rather than a functional regression in this patch. If you want, I can open a separate follow-up PR to make these workflows fork-safe (for example: skip on fork PRs, or split metadata-only actions into a safer trigger path).

[rwmjhb]

Closing: this has merge conflicts, and the change is too thin to justify as a standalone PR (+3/-3). If you'd like to contribute, consider bundling this into a more substantial testing improvement.