GHSA-QRWJ-VH9X-GW5V Coder's workspace agent API insecure redirect handling allowed cross-agent file read and write

Summary agentConn.apiClient used the default redirect behavior of http.Client while its custom transport dialed the host from the request URL as long as the port was the workspace agent HTTP API port 4. Agent tailnet IPs are deterministic from agent UUIDs, so a malicious workspace agent could...