chore(scripts): add dev-run helper

Co-authored-by: Cursor <cursoragent@cursor.com>

scripts/dev-run.sh

@@ -0,0 +1,16 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT_DIR="$(cd "$(dirname "$0")/.." && pwd)"
+PORT="${PORT:-80}"
+
+# On watchfiles restarts the previous process can linger briefly.
+# Proactively terminate any listener on the target port before boot.
+pids="$(ss -ltnp "sport = :$PORT" 2>/dev/null | sed -n 's/.*pid=\([0-9]\+\).*/\1/p' | sort -u)"
+if [ -n "${pids}" ]; then
+  kill -TERM ${pids} 2>/dev/null || true
+  sleep 0.3
+fi
+
+cd "$ROOT_DIR/src"
+exec python main.py