Remote-stack log streaming showed only "disconnected, 0 lines" whenever the
agent log proxy failed, because the LogViewer ignored type:"error" messages and
the proxy swallowed connection errors.
- ws.py: the agent-logs proxy now reports a clear, logged reason on failure —
distinguishes "cannot reach agent <url>" from a handshake rejection (HTTP 404
hints the agent is outdated and lacks live-log support) and forwards abnormal
upstream close codes (e.g. 4401 bad agent token).
- LogViewer: renders type:"error" messages (red) and surfaces a 4401 close as an
authorization error, instead of silently showing "Waiting for log output…".
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
