feat(start.sh): add stop and restart commands to manage services

Allows stopping/restarting services when ports are already in use,
with PID tracking, lsof fallback, and SIGKILL escalation.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

start.sh

@@ -4,19 +4,72 @@ set -e
 PROJECT_DIR="$(cd "$(dirname "$0")" && pwd)"
 BACKEND_DIR="$PROJECT_DIR/backend"
 FRONTEND_DIR="$PROJECT_DIR/frontend"
+PID_FILE="$PROJECT_DIR/.pids"
 
 # Colors
 GREEN='\033[0;32m'
 YELLOW='\033[1;33m'
+RED='\033[0;31m'
 NC='\033[0m'
 
-cleanup() {
-    echo -e "\n${YELLOW}Stopping services...${NC}"
-    kill $BACKEND_PID $FRONTEND_PID 2>/dev/null
-    wait $BACKEND_PID $FRONTEND_PID 2>/dev/null
-    echo -e "${GREEN}Done.${NC}"
+BACKEND_PORT=8000
+FRONTEND_PORT=5173
+
+stop_services() {
+    echo -e "${YELLOW}Stopping services...${NC}"
+    local stopped=0
+
+    # Kill by PID file first
+    if [ -f "$PID_FILE" ]; then
+        while read -r pid; do
+            if kill -0 "$pid" 2>/dev/null; then
+                kill "$pid" 2>/dev/null && stopped=1
+                echo -e "  Killed process $pid (from PID file)"
+            fi
+        done < "$PID_FILE"
+        rm -f "$PID_FILE"
+    fi
+
+    # Kill anything still on our ports
+    for port in $BACKEND_PORT $FRONTEND_PORT; do
+        local pids
+        pids=$(lsof -ti :"$port" 2>/dev/null || true)
+        if [ -n "$pids" ]; then
+            for pid in $pids; do
+                kill "$pid" 2>/dev/null && stopped=1
+                echo -e "  Killed process $pid on port $port"
+            done
+        fi
+    done
+
+    # Wait a moment for ports to free up
+    if [ "$stopped" -eq 1 ]; then
+        sleep 1
+    fi
+
+    # Verify ports are free
+    local still_busy=0
+    for port in $BACKEND_PORT $FRONTEND_PORT; do
+        if lsof -ti :"$port" >/dev/null 2>&1; then
+            echo -e "${RED}  Port $port still in use! Sending SIGKILL...${NC}"
+            kill -9 $(lsof -ti :"$port") 2>/dev/null || true
+            still_busy=1
+        fi
+    done
+    [ "$still_busy" -eq 1 ] && sleep 1
+
+    echo -e "${GREEN}Services stopped.${NC}"
 }
-trap cleanup EXIT
+
+start_services() {
+    # Check if ports are busy
+    for port in $BACKEND_PORT $FRONTEND_PORT; do
+        if lsof -ti :"$port" >/dev/null 2>&1; then
+            echo -e "${RED}Port $port is already in use!${NC}"
+            echo -e "${YELLOW}Use '$0 restart' to restart or '$0 stop' to stop first.${NC}"
+            exit 1
+        fi
+    done
 
     # Backend setup
     echo -e "${GREEN}[Backend] Setting up...${NC}"
@@ -34,8 +87,8 @@ if [ ! -f "$BACKEND_DIR/space_booking.db" ]; then
         cd "$BACKEND_DIR" && python seed_db.py
     fi
 
-echo -e "${GREEN}[Backend] Starting on :8000${NC}"
-cd "$BACKEND_DIR" && uvicorn app.main:app --reload --host 0.0.0.0 --port 8000 &
+    echo -e "${GREEN}[Backend] Starting on :${BACKEND_PORT}${NC}"
+    cd "$BACKEND_DIR" && uvicorn app.main:app --reload --host 0.0.0.0 --port $BACKEND_PORT &
     BACKEND_PID=$!
 
     # Frontend setup
@@ -44,14 +97,39 @@ if [ ! -d "$FRONTEND_DIR/node_modules" ]; then
         cd "$FRONTEND_DIR" && npm install --silent
     fi
 
-echo -e "${GREEN}[Frontend] Starting on :5173${NC}"
+    echo -e "${GREEN}[Frontend] Starting on :${FRONTEND_PORT}${NC}"
     cd "$FRONTEND_DIR" && npm run dev -- --host 0.0.0.0 &
     FRONTEND_PID=$!
 
+    # Save PIDs
+    echo "$BACKEND_PID" > "$PID_FILE"
+    echo "$FRONTEND_PID" >> "$PID_FILE"
+
     echo -e "\n${GREEN}=== Space Booking Running ===${NC}"
-echo -e "  Backend:  http://localhost:8000"
-echo -e "  Frontend: http://localhost:5173"
-echo -e "  API Docs: http://localhost:8000/docs"
+    echo -e "  Backend:  http://localhost:${BACKEND_PORT}"
+    echo -e "  Frontend: http://localhost:${FRONTEND_PORT}"
+    echo -e "  API Docs: http://localhost:${BACKEND_PORT}/docs"
     echo -e "${YELLOW}  Press Ctrl+C to stop${NC}\n"
 
+    trap 'stop_services; exit 0' EXIT INT TERM
     wait
+}
+
+# --- Main ---
+case "${1:-start}" in
+    start)
+        start_services
+        ;;
+    stop)
+        stop_services
+        ;;
+    restart)
+        stop_services
+        echo ""
+        start_services
+        ;;
+    *)
+        echo "Usage: $0 {start|stop|restart}"
+        exit 1
+        ;;
+esac