feat: wire systemd services to use centralized aitbc package

- Create wrapper scripts for all AITBC services using aitbc utilities
- Update 13 systemd service files to use wrapper scripts
- Wrapper scripts use aitbc constants (ENV_FILE, NODE_ENV_FILE, DATA_DIR, LOG_DIR, KEYSTORE_DIR)
- Services migrated: agent-coordinator, agent-daemon, agent-registry, blockchain-event-bridge, blockchain-node, blockchain-p2p, blockchain-rpc, blockchain-sync, coordinator-api, explorer, marketplace, wallet
- Add sys.path setup to cli/aitbc_cli.py for aitbc package access
- Centralized path management via aitbc package
- Consistent environment setup across all services

systemd/aitbc-blockchain-p2p.service

@@ -6,12 +6,11 @@ After=network.target
 Type=simple
 User=root
 Group=root
-WorkingDirectory=/opt/aitbc/apps/blockchain-node
+WorkingDirectory=/opt/aitbc
 Environment=PATH=/usr/bin:/usr/local/bin:/usr/bin:/bin
-Environment=PYTHONPATH=/opt/aitbc/apps/blockchain-node/src:/opt/aitbc/apps/blockchain-node/scripts
 EnvironmentFile=/etc/aitbc/.env
 EnvironmentFile=/etc/aitbc/node.env
-ExecStart=/opt/aitbc/venv/bin/python -m aitbc_chain.p2p_network --host ${p2p_bind_host} --port ${p2p_bind_port} --peers ${p2p_peers} --node-id ${p2p_node_id}
+ExecStart=/opt/aitbc/venv/bin/python /opt/aitbc/scripts/wrappers/aitbc-blockchain-p2p-wrapper.py
 Restart=always
 RestartSec=5
 StandardOutput=journal