e159a9b7ca
Breaking change: compute() returns null | { signal: T; workflow: WorkflowTrigger | null }
- WorkflowTrigger is a structured type (name, maxRounds, prompt, dryRun)
- Signal is always emitted before workflow launch (causal chain)
- CLI: nerve workflow trigger <name> --max-rounds N --prompt '...' --dry-run
- Remove pipe-separated directive format
Fixes #204