[turinglambdaai]

Closes #287 (the two items the matrix slice left open).

1. raco rivet verify-remote — orchestrate the remote legs from one editing host

raco rivet verify-remote --repo OWNER/REPO --ref <branch-or-sha> [--workflow verify.yml] [--platform linux]...

The command dispatches each platform's acceptance leg on GitHub Actions, waits for the dispatched runs, downloads the archived acceptance --json reports, and folds them into the shared matrix aggregation — so an agent editing on one OS receives the other platforms' evidence instead of assuming correctness from local results alone.

Design points:

• It drives the gh CLI and nothing else. Defaults (verify.yml, acceptance-report-<platform>) encode the convention the product CI guide documents; --workflow/--artifact-prefix/--platform/--timeout-seconds/--output-directory adapt it.
• Dispatch runs are identified against a pre-dispatch baseline (same workflow, same commit, unseen ids), so a concurrent session's runs can never be mistaken for this verification.
• Runs are collected keying off artifact names, not job names — a product's matrix workflow may name its jobs however it likes, and per-platform collection still works.
• A red run still hands over its archived evidence: the watch exit code only sets the conclusion, never skips the download, because the failing platform's report is exactly what the matrix exists to show.
• Exit code is green only when the matrix passes, every requested platform delivered a report, and no collection failed. --json adds per-run conclusions and report paths to the matrix document.
• Testable without a network: the entire gh boundary is injectable, and the tests script dispatch failures, delayed run lists, red legs, missing artifacts, timeouts, and argument validation against the real collection path.

The product CI guide (docs/ci.md, docs/ci.zh-CN.md) now archives every leg's report as acceptance-report-<platform> with if: always() — the exact convention the command consumes.

2. Classified evidence as first-class report fields

Manifest evidence entries accept a classified form alongside legacy strings:

(evidence . (#hasheq((path . ".rivet/acceptance/windows/ax.json")
                     (kind . accessibility-snapshot))
             #hasheq((path . ".rivet/acceptance/windows/screen.png")
                     (kind . screenshot))
             ".rivet/acceptance/windows/trace.json"))   ; generic

Kinds: accessibility-snapshot, screenshot, interaction-trace, log, generic (bare paths stay legal as generic). Accessibility snapshots are documented as the primary cross-platform record; screenshots are supplemental because native presentations are expected to differ.

The --json report now pins every declared entry's kind, presence, byte size, and SHA-256 — an archived report audits the artifacts it vouches for even when the files live in another platform's artifact store. missing-evidence stays for backward-compatible tooling.

Validation

• raco test rivet/tests/: 10110 tests pass locally (verify-remote +16 acceptance cases + all prior suites).
• raco rivet verify-remote --help dispatches through the lazy command loader; usage lists the command.