Add OpenSMTPD support for email server functionality

scripts/healthcheck.sh

@@ -172,6 +172,42 @@ main() {
         exit_code=1
     fi
 
+    # Check OpenSMTPD service (ports 25, 587, 465)
+    health_log "INFO" "=== OpenSMTPD Service ==="
+    OPENSMTPD_BINARY="/workspace/src/backend/app/opensmtpd/install/sbin/smtpd"
+    if [ -x "$OPENSMTPD_BINARY" ]; then
+        # Check SMTP port 25
+        if check_port 25 "SMTP"; then
+            health_log "INFO" "✓ SMTP port 25 is listening"
+        else
+            health_log "WARN" "⚠ SMTP port 25 is not listening (may be normal if not using inbound email)"
+        fi
+
+        # Check SMTP submission port 587
+        if check_port 587 "SMTP Submission"; then
+            health_log "INFO" "✓ SMTP submission port 587 is listening"
+        else
+            health_log "WARN" "⚠ SMTP submission port 587 is not listening"
+        fi
+
+        # Check SMTPS port 465
+        if check_port 465 "SMTPS"; then
+            health_log "INFO" "✓ SMTPS port 465 is listening"
+        else
+            health_log "WARN" "⚠ SMTPS port 465 is not listening"
+        fi
+
+        # Check OpenSMTPD process
+        if pgrep -f "smtpd" > /dev/null; then
+            local smtpd_pid=$(pgrep -f "smtpd" | head -1)
+            health_log "INFO" "✓ OpenSMTPD process running (PID: ${smtpd_pid})"
+        else
+            health_log "WARN" "⚠ OpenSMTPD process not found (may be disabled)"
+        fi
+    else
+        health_log "INFO" "OpenSMTPD not installed at expected location, skipping SMTP checks"
+    fi
+
     # ttyd service has been removed, no longer checking port 4501
 
     health_log "INFO" "========== HEALTH CHECK END ==========="