feat(t100): durable per-device client prefs

[duongdev]

What

Three web-only client prefs — qualityTier, inputTransport, latencyHud — moved off localStorage (which resets on the iPad PWA) into per-device server ui-state, keyed <base>_<deviceId> (same seam as webPush/notifMutes, t093/t095). Each web device now keeps its own values and they survive a PWA refresh/reinstall. Also kills a live drift bug where qualityTier was double-stored (localStorage vs the global the connector reads).

Spec + rationale: docs/tasks/done/100-durable-per-device-client-prefs.md.

How

• New pure module src/lib/device-prefs.ts (TDD) — the single owner of the plain↔<base>_<deviceId> remap, defaults, parse-guards, and the qualityTier global-shadow rule: a tier write also mirrors the plain global key the shared-screencast connector reads, so the connecting device's tier applies to the one shared stream with core/remote-page-connector.js byte-unchanged.
• core/settings-store.js DEVICE_KEY_PREFIXES gains the 3 prefixes; cdp-web-transport.ts resolves/remaps them in getUiState/setUiState and sources the transport mode from ui-state (boots auto, reconfigures once when ui-state lands).
• settings-dialog.tsx / latency-hud.tsx / app.tsx read/write ui-state; the transport-selector's transient last-good probe cache intentionally stays in localStorage (not a durable pref).
• Migration is implicit: a device with no qualityTier slot falls back to the existing global value → nothing resets on first load after ship.

Notes

• A polish pass caught a regression: dropping the qualityTier localStorage key broke viewport.tsx's resize reissue (it read that key to preserve the tier on Page.startScreencast, t099). Fixed with a live in-memory tier mirror in quality-tier.ts, seeded from ui-state at boot + on picker change.
• Electron is byte-unchanged (all three prefs are web-only).
• No visual delta — pickers/switch/labels are identical; on-device restore-after-relaunch folds into the standard prod device check.

Tests

typecheck · 1014 unit (+device-prefs 17, quality-tier mirror 3, settings-store 1) · 49 e2e (+2 real-server ui-state round-trip proving persistence + device isolation) · build · biome clean on touched files.

https://claude.ai/code/session_01USyifc9ZK6Cy5hAmKKy2ok

[dokploy-2026-03-01-6ei3s7]

Dokploy Preview Deployment

Name	Status	Preview	Updated (UTC)
cdp-browser-app	✅ Done	Preview URL	2026-07-07T10:37:42.450Z