Replace DHT-based discovery with bootstrap peerstore and peer exchange.
Update config and code to remove DHT references and dependencies. Add
data directory override support in node config. Cleanup related config
files and dependencies.
- Remove configmap.go and bootstrap-specific config logic
- Refactor main.go to use a unified node startup for all roles
- Remove DHT and mDNS from config and node logic; use bootstrap + peer
exchange
- Update constants to extract bootstrap peer IDs from addresses
- Simplify RQLite advertise logic and remove external IP detection
- Add zeroconf as indirect dependency
- Remove environment variable overrides from config
- Update README with port usage clarification
- Add new CLI and node binaries
