fix(weixin): clarify login progress and harden iLink polling

[bobleer]

Summary

WeChat phone confirmation can leave the desktop looking frozen while iLink holds a QR status request open. Show scan, confirmation, and bot startup progress with delayed waiting guidance, and harden the login and message transport against the official @tencent-weixin/openclaw-weixin 2.4.8 contract.

Type and Areas

Type: Bug fix / UI/UX

Areas: Web UI, remote-connect integration service, Core WeChat bot orchestration.

Motivation / Impact

• Explain the current login phase and longer waits in English, Simplified Chinese, and Traditional Chinese. Preserve the six-digit pairing flow and cancellation lifecycle.
• Reuse HTTP clients, serialize overlapping QR polls, and retain confirmed results for retry within the login session TTL.
• Continue receiving immediately after a normal long-poll timeout, preserve nonempty receive cursors, and handle stale login tokens as failures.
• Reject malformed send responses and provider application errors instead of reporting successful delivery.

Verification

• cargo test --locked -p openbitfun-services-integrations --no-default-features --features remote-connect --lib remote_connect::bot::weixin::tests:: — 20 passed. Loopback fixtures cover QR transitions, verification, refresh, overlapping polls and replay, timeout/cursor behavior, stale tokens, and outbound payload/error handling.
• cargo test --locked -p openbitfun-core --no-default-features --features remote-connect --lib service::remote_connect::bot::weixin::tests:: — 3 passed.
• NODE_OPTIONS=--no-experimental-webstorage pnpm --dir src/web-ui exec vitest run src/app/components/RemoteConnectDialog/WeixinLoginProgress.test.tsx src/app/components/RemoteConnectDialog/RemotePairingCard.test.tsx src/app/components/RemoteConnectDialog/RemoteConnectDialog.contract.test.ts src/app/components/RemoteConnectDialog/remoteConnectOperationCleanup.test.ts --maxWorkers=50% — 40 passed.
• pnpm check:web — passed, including type and theme checks.
• pnpm i18n:audit — passed with no warnings.
• pnpm motion:audit — reviewed inventory; no new motion debt.
• pnpm run fmt:rs and git diff --check — passed.

Reviewer Notes

Reference: https://www.npmjs.com/package/@tencent-weixin/openclaw-weixin (2.4.8).

The provider remains platform-neutral. No persisted or public wire fields change. Tests exercise local simulated iLink transport and controller retry behavior; live WeChat, remote workspace, mobile/IM remote control, Peer Device Mode, and Detached Dispatch were not exercised end to end.

Checklist

• This PR is focused and does not include secrets, temporary prompts, generated scratch files, or unrelated artifacts.
• Relevant verification is recorded above, or skipped checks are explained.
• User-facing strings, docs, and locales are updated where applicable.