[Jumpstile]

Summary

• Add a TV-friendly Live Now screen backed by the versioned, read-only One Guide API, including bounded pagination and fail-closed response checks.
• Add accessible programme cards, UTC times, keyboard navigation, details/back focus restoration, loading/empty/error/retry states, and no playback or tuning action.
• Derive One Guide TypeScript output types from the canonical JSON Schema and generate an Ajv standalone validator at development time. The checked-in generated validator uses static imports and no runtime eval/Function, compatible with the WebView CSP.
• Correct Windows Task Scheduler platform detection to use the runtime platform API rather than $env:OS; add a regression test. This fixed the pinned full-suite run on a Windows host where $env:OS is absent.
• Record API/UI performance evidence and fixture/hardware caveats in engineering docs.

Closes #200.

Verification

• Pester 5.7.1 with $env:OS absent: 870 passed, 0 failed.
• GUI: 96 unit tests passed; TypeScript typecheck and production build passed. Schema drift check passed.
• Chromium E2E: 10 passed, including axe checks for list/details, GET-only API behavior, pagination, keyboard navigation, details and focus restoration.
• Production-preview fixture run: first visible content 173.7 ms, full list 179.2 ms; mock API resource durations 6.6 ms and 5.4 ms.
• Warm in-process API route against a temporary accepted-guide fixture, 40 samples/page: 100-item page p50 80.00 ms / p95 89.48 ms; final 1-item page p50 18.10 ms / p95 22.52 ms. Not HTTP-socket or SER8 measurements.
• Changed documentation/manifests pass targeted Prettier. The root Prettier command locally also scans ignored Tauri-generated schemas/build output, which fail formatting; the hosted CI run on the clean checkout remains authoritative for that root gate.

Local GUI checks ran under Node 26.10.0, outside gui/package.json's Node >=22 <23 range. .github/workflows/powershell-ci.yml pins Node 22; hosted CI remains the supported-runtime check.

Product intent-fit audit

• Intended behavior: show currently-airing accepted-guide entries; allow safe details navigation; do not start playback or change state.
• Entry points: gui/src/App.tsx, gui/src/app/navigation.ts, gui/src/app/oneGuide.ts, gui/src/pages/LiveNowPage.tsx, and the existing versioned /api/one-guide read routes in Get-ChannelForgeWebResponse.
• Safety boundary: read-only GETs over the accepted One Guide projection. No provider requests, playback/tuning, accepted-state mutation, guide publication, downstream writes, or output-file writes. The client validates full schema fields plus query and cross-page pagination invariants.
• Redaction: UI displays safe title/category/source/time fields; it does not render raw IDs, hashes, provider URLs, private paths, or backend error details.
• Disposition: PASS. Performance numbers use fixtures; no SER8 hardware measurement is claimed or required for this UI slice.