fix(harmony): make remote connections resumable

[wgqqqqq]

Summary

• unlock the complete chat/settings shell as soon as QR pairing succeeds; show QR access as a temporary identity in Settings and open account sign-in only when the user selects that identity card
• expose the active desktop as an independent Settings card; QR connections can be explicitly ended and forgotten without logging out the phone account, while offline remembered targets remain reconnectable
• persist the last successful control transport separately from the remembered account device, so HarmonyOS cold start restores the intended route
• keep an established QR room alive across desktop account login, replacement, logout, and expiry; rotate only an unpaired invitation whose encoded authentication mode became stale
• keep an active QR room alive when the phone account logs out or expires, and allow QR-to-account recovery only for the same physical desktop on the same relay
• isolate concurrent QR/account connection attempts, complete initial synchronization before publishing a transport, and keep transient failures retryable
• preserve composer drafts during model selection, replace the model sheet with a keyboard-safe anchored menu, and keep supplemental voice input available beside existing text
• preserve HarmonyOS bundle and encrypted-storage identities across the OpenBitFun rename

Verification

• pnpm run harmony:architecture
• HarmonyOS local unit tests through hvigor
• pnpm run i18n:audit
• pnpm run theme:color-audit:all
• signed HarmonyOS HAP build through hvigor
• installed and launched the signed HAP on USB device 5ZU0226202001116
• cargo test -p openbitfun-desktop --lib (395 passed, 4 ignored)
• focused desktop account-boundary test rerun after rebasing onto the latest base
• pnpm run check:web
• git diff --check

pnpm run check:repo-hygiene is locally blocked only by eight untracked HarmonyOS device screenshots/layout dumps; those files are not part of this PR.

Remote scenarios

• Remote control: exercised by desktop lifecycle tests, Harmony transport/startup/presentation tests, signed HAP build, and physical-device install
• Peer Device Mode: same-device account fallback, target restore, offline retry, and transport replacement paths are covered by Harmony tests
• Remote workspace and Detached Dispatch: no behavior changed