Add agentd daemon subcommand to run the HTTP API server.
Current state:
Target state:
agentd daemon starts the HTTP server on configurable portagentd daemon --port 8400 --db /var/lib/omni/agentd.dbImplementation: 1. Add DaemonCmd to Agentd.hs CLI parser 2. Wire up to Daemon.runDaemon 3. Add config flags: --port, --db-path, --log-root, --workspace 4. Document in SPEC.md
Updated agentd daemon CLI to accept --pi-path and pass dcPiPath into DaemonConfig; verified with typecheck.sh Omni/Agentd.hs. Daemon command was already present.