Remote Workflow Launch via Server Events (CCR)

Claude Code Remote sessions can now receive workflow_launch SSE events from the server, which trigger automatic workflow execution. This enables server-initiated multi-agent workflows in remote sessions without requiring a user to type a command.

The flow:

1. Server pushes a workflow_launch event with a signed workflow bundle (filestore path + SHA256)
2. Claude Code fetches the bundle, verifies the SHA256, and validates the format (version byte, script frame, args frame)
3. If all checks pass, the script is executed via the workflow engine
4. Results are posted back to the server as a workflow_launch_result system event

Policy gates:

• Blocked entirely if disableWorkflows is set in managed settings (separate message from org policy block)
• Blocked if org policy allow_workflows is false
• At most one workflow_launch event per session is permitted

The CLAUDE_CODE_REMOTE_SESSION_ORIGIN env var (set to "review") bypasses the org policy check for server-authored carriers.