chore: initialize monorepo with project scaffolding, configs, and CI setup

apps/blockchain-node/scripts/devnet_up.sh

@@ -0,0 +1,36 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+export PYTHONPATH="${ROOT_DIR}/src:${ROOT_DIR}/scripts:${PYTHONPATH:-}"
+
+GENESIS_PATH="${ROOT_DIR}/data/devnet/genesis.json"
+python "${ROOT_DIR}/scripts/make_genesis.py" --output "${GENESIS_PATH}" --force
+
+echo "[devnet] Generated genesis at ${GENESIS_PATH}"
+
+declare -a CHILD_PIDS=()
+cleanup() {
+  for pid in "${CHILD_PIDS[@]}"; do
+    if kill -0 "$pid" 2>/dev/null; then
+      kill "$pid" 2>/dev/null || true
+    fi
+  done
+}
+trap cleanup EXIT
+
+python -m aitbc_chain.main &
+CHILD_PIDS+=($!)
+echo "[devnet] Blockchain node started (PID ${CHILD_PIDS[-1]})"
+
+sleep 1
+
+python -m uvicorn aitbc_chain.app:app --host 127.0.0.1 --port 8080 --log-level info &
+CHILD_PIDS+=($!)
+echo "[devnet] RPC API serving at http://127.0.0.1:8080" 
+
+python -m uvicorn mock_coordinator:app --host 127.0.0.1 --port 8090 --log-level info &
+CHILD_PIDS+=($!)
+echo "[devnet] Mock coordinator serving at http://127.0.0.1:8090" 
+
+wait