feat(hub): improve WHOIS lookup reliability and enhance site UI

Implement enhanced WHOIS lookup strategies, specifically targeting .eu
domains through EURid web scraping and alternative services to
improve data accuracy for expiry dates.

- Add EURid web scraping and alternative WHOIS service support for .eu domains
- Increase timeouts for .eu domain lookups in TCP and native WHOIS
- Improve domain scheduler to prevent overwriting valid data with zero-value dates
- Enhance site UI with subdomain indicators in domain tables
- Add filtering capabilities to the calendar view
- Implement drag-and-drop reordering for systems table
- Add new debug and test utilities for WHOIS and date parsing logic

test/tcp_whois_debug.go

@@ -0,0 +1,112 @@
+package main
+
+import (
+	"fmt"
+	"net"
+	"strings"
+	"time"
+)
+
+func main() {
+	// Test TCP WHOIS for .eu domains
+	testDomains := []string{"bookra.eu", "sportcreative.eu"}
+
+	for _, domainName := range testDomains {
+		fmt.Printf("Testing TCP WHOIS for: %s\n", domainName)
+		fmt.Println("----------------------------------------")
+
+		// Extract TLD
+		parts := strings.Split(domainName, ".")
+		if len(parts) < 2 {
+			fmt.Printf("Invalid domain format: %s\n", domainName)
+			continue
+		}
+		tld := strings.ToLower(parts[len(parts)-1])
+
+		// WHOIS server for .eu
+		server := "whois.eu"
+		if tld != "eu" {
+			fmt.Printf("Skipping non-eu domain: %s\n", domainName)
+			continue
+		}
+
+		addr := net.JoinHostPort(server, "43")
+		fmt.Printf("Connecting to: %s\n", addr)
+
+		// Use longer timeout for .eu domains
+		timeout := 20 * time.Second
+		dialer := &net.Dialer{Timeout: timeout}
+
+		start := time.Now()
+		conn, err := dialer.Dial("tcp", addr)
+		if err != nil {
+			fmt.Printf("TCP WHOIS dial failed: %v\n", err)
+			continue
+		}
+		defer conn.Close()
+
+		fmt.Printf("Connected in: %v\n", time.Since(start))
+
+		// Send query
+		query := domainName + "\r\n"
+		fmt.Printf("Sending query: %q\n", query)
+
+		writeStart := time.Now()
+		if _, err := conn.Write([]byte(query)); err != nil {
+			fmt.Printf("TCP WHOIS write failed: %v\n", err)
+			continue
+		}
+		fmt.Printf("Write completed in: %v\n", time.Since(writeStart))
+
+		// Set read deadline
+		if err := conn.SetReadDeadline(time.Now().Add(timeout)); err != nil {
+			fmt.Printf("Failed to set read deadline: %v\n", err)
+			continue
+		}
+
+		// Read response
+		var output strings.Builder
+		buf := make([]byte, 4096)
+		totalRead := 0
+
+		readStart := time.Now()
+		for {
+			n, err := conn.Read(buf)
+			if n > 0 {
+				output.Write(buf[:n])
+				totalRead += n
+				fmt.Printf("Read %d bytes (total: %d)\n", n, totalRead)
+			}
+			if err != nil {
+				if err.Error() != "EOF" {
+					fmt.Printf("Read error: %v\n", err)
+				}
+				break
+			}
+			// Prevent infinite loop
+			if totalRead > 10000 {
+				fmt.Printf("Stopping read after 10KB\n")
+				break
+			}
+		}
+
+		fmt.Printf("Read completed in: %v\n", time.Since(readStart))
+		fmt.Printf("Total bytes read: %d\n", totalRead)
+
+		response := output.String()
+		if len(response) > 0 {
+			fmt.Printf("✅ WHOIS Response (first 500 chars):\n")
+			if len(response) > 500 {
+				fmt.Printf("%s...\n", response[:500])
+			} else {
+				fmt.Printf("%s\n", response)
+			}
+		} else {
+			fmt.Printf("❌ No response received\n")
+		}
+
+		fmt.Println()
+		fmt.Println("========================================")
+		fmt.Println()
+	}
+}