fix(6): standalone launcher improvements

- Use uvicorn CLI directly (not python -c workaround)
- Add process group handling for cleaner shutdown
- Silent npm output during setup
- Better error messages and logging
- Support graceful SIGTERM/SIGINT handling

start_servers.py

@@ -10,7 +10,6 @@ import sys
 import subprocess
 import signal
 import time
-import json
 from pathlib import Path
 
 
@@ -106,32 +105,36 @@ class StandaloneServerManager:
             subprocess.run(
                 ["npm", "ci", "--silent"],
                 cwd=str(frontend_dir),
-                check=True
+                check=True,
+                capture_output=True
             )
 
         # Build if needed
-        if not (frontend_dir / ".next").exists():
+        if not (frontend_dir / ".next" / "standalone").exists():
             self.log("Building Next.js application...")
             subprocess.run(
                 ["npm", "run", "build"],
                 cwd=str(frontend_dir),
-                check=True
+                check=True,
+                capture_output=True
             )
 
     def start_backend(self):
-        """Start FastAPI backend server"""
+        """Start FastAPI backend server using uvicorn directly from project root"""
         self.log(f"Starting backend on port {self.backend_port}...")
         backend_log = self.logs_dir / "backend.log"
-
         backend_dir = self.root_dir / "backend"
+
         env = os.environ.copy()
         env['PATH'] = f"{self.python_exe.parent}:{env['PATH']}"
 
+        # Use uvicorn CLI from venv to run the app
         with open(backend_log, 'w') as log_f:
             self.backend_process = subprocess.Popen(
                 [
                     str(self.python_exe),
-                    "-m", "uvicorn",
+                    "-m",
+                    "uvicorn",
                     "main:app",
                     "--host", "0.0.0.0",
                     "--port", str(self.backend_port),
@@ -140,7 +143,8 @@ class StandaloneServerManager:
                 cwd=str(backend_dir),
                 stdout=log_f,
                 stderr=subprocess.STDOUT,
-                env=env
+                env=env,
+                preexec_fn=os.setsid  # Create new process group to avoid signal issues
             )
 
         self.log(f"✓ Backend started (PID: {self.backend_process.pid})")
@@ -153,6 +157,7 @@ class StandaloneServerManager:
 
         env = os.environ.copy()
         env['PORT'] = str(self.frontend_port)
+        env['NODE_ENV'] = 'production'
 
         with open(frontend_log, 'w') as log_f:
             self.frontend_process = subprocess.Popen(
@@ -160,7 +165,8 @@ class StandaloneServerManager:
                 cwd=str(frontend_dir),
                 stdout=log_f,
                 stderr=subprocess.STDOUT,
-                env=env
+                env=env,
+                preexec_fn=os.setsid  # Create new process group
             )
 
         self.log(f"✓ Frontend started (PID: {self.frontend_process.pid})")
@@ -205,8 +211,7 @@ class StandaloneServerManager:
         print(f"  Frontend:   tail -f {self.logs_dir / 'frontend.log'}")
         print(f"  All logs:   tail -f {self.logs_dir}/*.log")
         print("\nTo stop servers:")
-        print(f"  kill {self.backend_process.pid} {self.frontend_process.pid}")
-        print("\nPress Ctrl+C to stop both servers")
+        print(f"  Press Ctrl+C in this terminal")
         print("="*60 + "\n")
 
     def run(self):
@@ -225,14 +230,16 @@ class StandaloneServerManager:
             self.print_summary()
 
             # Monitor processes
-            self.log("✓ Servers are running!")
+            self.log("✓ Servers are running! Press Ctrl+C to stop.")
             while True:
                 # Check if processes are alive
                 if self.backend_process.poll() is not None:
                     self.log(f"⚠ Backend process exited with code {self.backend_process.returncode}")
+                    self.log("  Check logs/backend.log for details")
 
                 if self.frontend_process.poll() is not None:
                     self.log(f"⚠ Frontend process exited with code {self.frontend_process.returncode}")
+                    self.log("  Check logs/frontend.log for details")
 
                 time.sleep(5)
 
@@ -244,19 +251,27 @@ class StandaloneServerManager:
 
     def cleanup(self):
         """Gracefully shutdown servers"""
+        import signal
+
         if self.backend_process:
             try:
-                self.backend_process.terminate()
+                os.killpg(os.getpgid(self.backend_process.pid), signal.SIGTERM)
                 self.backend_process.wait(timeout=5)
-            except subprocess.TimeoutExpired:
-                self.backend_process.kill()
+            except Exception:
+                try:
+                    self.backend_process.kill()
+                except Exception:
+                    pass
 
         if self.frontend_process:
             try:
-                self.frontend_process.terminate()
+                os.killpg(os.getpgid(self.frontend_process.pid), signal.SIGTERM)
                 self.frontend_process.wait(timeout=5)
-            except subprocess.TimeoutExpired:
-                self.frontend_process.kill()
+            except Exception:
+                try:
+                    self.frontend_process.kill()
+                except Exception:
+                    pass
 
         self.log("✓ Servers stopped")
         sys.exit(0)