fix: enhance gateway logging for Windows dev restart debugging (#665)

Add comprehensive debug logging throughout the gateway lifecycle to
help troubleshoot nodemon restart issues on Windows, where SIGTERM
is used instead of SIGUSR2.

Changes:
- Enhanced shutdown handler to log all signals and env var states
- Gateway manager now logs process detachment mode explicitly
- Added environment variable confirmation on bootstrap
- Updated gateway-development.md with new debug logs and troubleshooting steps

Benefits:
- Easier troubleshooting of gateway lifecycle issues
- Clear visibility into signal handling during nodemon restarts
- Better cross-platform development experience
- Production behavior remains unchanged

Testing:
- ✅ Windows: Gateways persist across nodemon restarts
- ✅ macOS/Linux: Existing SIGUSR2 behavior preserved
- ✅ Production: Default shutdown cleanup unchanged
- ✅ Backward compatibility: No breaking changes

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/server/src/services/hermes/gateway-manager.ts

@@ -148,8 +148,18 @@ function isLocalHost(host: string): boolean {
 }
 
 function shouldDetachGatewayProcess(): boolean {
+  // In dev mode (nodemon), always detach gateway processes so they survive restarts
+  // Production mode: attach gateways so they can be managed together with the server
   const override = process.env.HERMES_WEB_UI_STOP_GATEWAYS_ON_SHUTDOWN?.trim().toLowerCase()
-  return override === '0' || override === 'false'
+  const shouldDetach = override === '0' || override === 'false'
+
+  if (shouldDetach) {
+    console.log('[gateway] Detaching gateway process (dev mode: HERMES_WEB_UI_STOP_GATEWAYS_ON_SHUTDOWN=' + override + ')')
+  } else {
+    console.log('[gateway] Attaching gateway process (prod mode: HERMES_WEB_UI_STOP_GATEWAYS_ON_SHUTDOWN=' + (override || 'not set') + ')')
+  }
+
+  return shouldDetach
 }
 
 // ============================

packages/server/src/services/shutdown.ts

@@ -6,10 +6,25 @@ function shouldStopGatewaysOnShutdown(signal: string): boolean {
   // nodemon may use SIGTERM on Windows restarts, so dev mode opts out via env.
   // Production keeps stopping owned gateways by default.
   const override = process.env.HERMES_WEB_UI_STOP_GATEWAYS_ON_SHUTDOWN?.trim()
-  if (override === '0' || override === 'false') return false
-  if (override === '1' || override === 'true') return true
 
-  return signal !== 'SIGUSR2'
+  console.log(`[shutdown] Signal: ${signal}, HERMES_WEB_UI_STOP_GATEWAYS_ON_SHUTDOWN: ${override}`)
+
+  // Explicit '0' or 'false' means dev mode: never stop gateways
+  if (override === '0' || override === 'false') {
+    console.log('[shutdown] Dev mode detected: NOT stopping gateways')
+    return false
+  }
+
+  // Explicit '1' or 'true' means always stop gateways
+  if (override === '1' || override === 'true') {
+    console.log('[shutdown] Explicit gateway shutdown enabled: stopping gateways')
+    return true
+  }
+
+  // Default behavior: only stop gateways on explicit termination, not on reload
+  const shouldStop = signal !== 'SIGUSR2'
+  console.log(`[shutdown] Default behavior: ${shouldStop ? 'STOPPING' : 'NOT stopping'} gateways (signal: ${signal})`)
+  return shouldStop
 }
 
 export function bindShutdown(server: any, groupChatServer?: any, chatRunServer?: any): void {
@@ -23,6 +38,9 @@ export function bindShutdown(server: any, groupChatServer?: any, chatRunServer?:
     setTimeout(() => process.exit(0), 3000)
 
     logger.info('Shutting down (%s)...', signal)
+    console.log(`[shutdown] Received signal: ${signal}`)
+    console.log(`[shutdown] HERMES_WEB_UI_STOP_GATEWAYS_ON_SHUTDOWN = ${process.env.HERMES_WEB_UI_STOP_GATEWAYS_ON_SHUTDOWN}`)
+    console.log(`[shutdown] shouldStopGatewaysOnShutdown = ${shouldStopGatewaysOnShutdown(signal)}`)
 
     try {
       if (shouldStopGatewaysOnShutdown(signal)) {