Initialize hub title bar status on bind

[ranjeshj]

Summary

• Initialize the HubWindow title bar status when binding to AppState so tray-launched windows reflect the current connection immediately.
• Keeps subsequent updates on the existing AppState PropertyChanged path.

Hanselman review

Issue	Opus	Codex	Consensus	Fix confidence
No correctness issues found in scoped change	—	—	HIGH	99%

Validation

• ./build.ps1
• dotnet test ./tests/OpenClaw.Shared.Tests/OpenClaw.Shared.Tests.csproj --no-restore
• dotnet test ./tests/OpenClaw.Tray.Tests/OpenClaw.Tray.Tests.csproj --no-restore