Keep long-running turns visible and connected

[teempai]

Summary

• give harness message submissions the same 24-hour relay bridge deadline as the native loopback client, preventing false 502s while Codex, Claude, or Hermes continues working
• keep the working cue below the sent message initially, then pin it above the composer after later agent output arrives so progress remains visible
• reconcile optimistic user messages by client message ID so the canonical copy does not render beside a duplicate pending copy

Verification

• PATH=/opt/homebrew/bin:$PATH npm run typecheck
• PATH=/opt/homebrew/bin:$PATH npm run build
• PATH=/opt/homebrew/bin:$PATH npm test (300/300)
• swift test (56/56)
• macOS EXARCHMac Xcode build
• iOS Simulator EXARCH Xcode build