feat(web): polish remote chat app surfaces

[bobleer]

Summary

• replace generic chat glyphs across the overview, provider tabs, nav status, and device overview with the real monochrome Telegram, Feishu, and WeChat marks
• redesign the connected chat-app panel around app identity, connection state, channel notice, mode control, and a quieter disconnect action
• tighten the device overview hierarchy, icon containers, spacing, and manage-devices action
• localize the connected chat-app description and protect the branded-icon integration with a contract test

Verification

• pnpm --dir src/web-ui run test:run src/app/components/RemoteConnectDialog/RemoteConnectDialog.contract.test.ts src/app/components/NavPanel/deviceInterconnectionOverview.test.ts (48 tests)
• pnpm run i18n:audit
• pnpm run motion:audit
• pnpm run check:web
• browser visual QA at the desktop dialog and device-overview popover

Remote scenarios

• Local desktop: exercised in the Vite desktop surface.
• Remote control: Weixin and Telegram controller projections are covered by focused tests; no wire behavior changed.
• Remote workspace, Peer Device Mode, Detached Dispatch: no behavior or protocol changes.