Open Pstack 1.17.1

Updates four engineering principles to use evidence and observable contracts instead of blanket recipes:

• Test the shared premise directly before trying another fix.
• Handle legitimate missing state where it belongs, and trace invalid state to its producer.
• Reconcile actual state across retries and judge stale ownership with evidence.
• Keep tests that catch broken behavior and survive internal refactors, including valid absence, external-payload, invariant and public-diagnostic contracts.

Correct and Poteto summaries match these principles. Portable host metadata, saved model descriptors and efforts, spending/recovery policy, provider behavior and parent Git ownership remain unchanged.

Cursor source is e5136d82418d2db3165ea1050d17577cd618cc05, still version 0.15.25. This same-version content update maps to this distribution’s next patch 1.17.1 under the standing catch-up policy. PR #142 records adoption decisions and evidence. See the release-pinned provenance.

Validation includes normal-budget Linux CI with 953 Bun tests passing, 5 skipped and 0 failing, plus maintenance, hook and documentation checks. Both real native hosts loaded the candidate, executed the supplied control and correctly distinguished the changed cases; Claude invoked all four registered principle skills. The 235 packaged files were verified in both dedicated installations. Independent Opus source review passed; the independent native shipping review passed with notes. Its reconciliation records the later CI evidence and the retained local failures.

Limits: the host scenarios use supplied deterministic controls and requirements, not production timing, actual filesystem/process crashes or a universal model-behavior evaluation. No source correction to the fixture’s renderer/decoder was implemented. Local default-budget tests timed out in unchanged frontier fixtures; an explicitly larger-budget run later failed an unchanged Grok retry-deadline fixture. Both failures are retained in issue #141; no test or runtime source was changed to hide them. Linux CI passed with normal settings.

Previous immutable release v1.17.0 is the rollback checkpoint. See the release-pinned UPSTREAM.md and source ledger for provenance.