Refactor server package: split handlers and routes into separate files

- Move all handler functions to handlers.go
- Move setupRoutes to routes.go
- Clean up server.go to only contain core server logic
- Add missing GetASDetails and GetPrefixDetails to mockStore for tests
- Fix linter errors (magic numbers, unused parameters, blank lines)

internal/database/database.go

@@ -743,3 +743,101 @@ func CalculateIPv4Range(cidr string) (start, end uint32, err error) {
 
 	return start, end, nil
 }
+
+// GetASDetails returns detailed information about an AS including prefixes
+func (d *Database) GetASDetails(asn int) (*ASN, []LiveRoute, error) {
+	// Get AS information
+	var asnInfo ASN
+	var idStr string
+	var handle, description sql.NullString
+	err := d.db.QueryRow(
+		"SELECT id, number, handle, description, first_seen, last_seen FROM asns WHERE number = ?",
+		asn,
+	).Scan(&idStr, &asnInfo.Number, &handle, &description, &asnInfo.FirstSeen, &asnInfo.LastSeen)
+
+	if err != nil {
+		if err == sql.ErrNoRows {
+			return nil, nil, fmt.Errorf("%w: AS%d", ErrNoRoute, asn)
+		}
+
+		return nil, nil, fmt.Errorf("failed to query AS: %w", err)
+	}
+
+	asnInfo.ID, _ = uuid.Parse(idStr)
+	asnInfo.Handle = handle.String
+	asnInfo.Description = description.String
+
+	// Get prefixes announced by this AS
+	query := `
+		SELECT DISTINCT prefix, mask_length, ip_version, last_updated
+		FROM live_routes
+		WHERE origin_asn = ?
+		ORDER BY ip_version, mask_length, prefix
+	`
+
+	rows, err := d.db.Query(query, asn)
+	if err != nil {
+		return &asnInfo, nil, fmt.Errorf("failed to query prefixes: %w", err)
+	}
+	defer func() { _ = rows.Close() }()
+
+	var prefixes []LiveRoute
+	for rows.Next() {
+		var route LiveRoute
+		err := rows.Scan(&route.Prefix, &route.MaskLength, &route.IPVersion, &route.LastUpdated)
+		if err != nil {
+			continue
+		}
+		route.OriginASN = asn
+		prefixes = append(prefixes, route)
+	}
+
+	return &asnInfo, prefixes, nil
+}
+
+// GetPrefixDetails returns detailed information about a prefix
+func (d *Database) GetPrefixDetails(prefix string) ([]LiveRoute, error) {
+	query := `
+		SELECT lr.origin_asn, lr.peer_ip, lr.as_path, lr.next_hop, lr.last_updated,
+			   a.handle, a.description
+		FROM live_routes lr
+		LEFT JOIN asns a ON a.number = lr.origin_asn
+		WHERE lr.prefix = ?
+		ORDER BY lr.origin_asn, lr.peer_ip
+	`
+
+	rows, err := d.db.Query(query, prefix)
+	if err != nil {
+		return nil, fmt.Errorf("failed to query prefix details: %w", err)
+	}
+	defer func() { _ = rows.Close() }()
+
+	var routes []LiveRoute
+	for rows.Next() {
+		var route LiveRoute
+		var pathJSON string
+		var handle, description sql.NullString
+
+		err := rows.Scan(
+			&route.OriginASN, &route.PeerIP, &pathJSON, &route.NextHop,
+			&route.LastUpdated, &handle, &description,
+		)
+		if err != nil {
+			continue
+		}
+
+		// Decode AS path
+		if err := json.Unmarshal([]byte(pathJSON), &route.ASPath); err != nil {
+			route.ASPath = []int{}
+		}
+
+		route.Prefix = prefix
+		routes = append(routes, route)
+	}
+
+	if len(routes) == 0 {
+		return nil, fmt.Errorf("%w: %s", ErrNoRoute, prefix)
+	}
+
+	return routes, nil
+}

internal/database/interface.go

@@ -47,6 +47,10 @@ type Store interface {
 	// IP lookup operations
 	GetASInfoForIP(ip string) (*ASInfo, error)
 
+	// AS and prefix detail operations
+	GetASDetails(asn int) (*ASN, []LiveRoute, error)
+	GetPrefixDetails(prefix string) ([]LiveRoute, error)
+
 	// Lifecycle
 	Close() error
 }