Fix linting errors for magic numbers in handler queue sizes

- Define constants for all handler queue capacities
- Fix integer overflow warning in metrics calculation
- Add missing blank lines before continue statements

internal/routewatch/dbhandler.go

@@ -7,6 +7,11 @@ import (
 	"git.eeqj.de/sneak/routewatch/internal/ristypes"
 )
 
+const (
+	// databaseHandlerQueueSize is the queue capacity for database operations
+	databaseHandlerQueueSize = 100
+)
+
 // DatabaseHandler handles BGP messages and stores them in the database
 type DatabaseHandler struct {
 	db     database.Store
@@ -27,6 +32,12 @@ func (h *DatabaseHandler) WantsMessage(messageType string) bool {
 	return messageType == "UPDATE"
 }
 
+// QueueCapacity returns the desired queue capacity for this handler
+func (h *DatabaseHandler) QueueCapacity() int {
+	// Database operations are slow, so use a smaller queue
+	return databaseHandlerQueueSize
+}
+
 // HandleMessage processes a RIS message and updates the database
 func (h *DatabaseHandler) HandleMessage(msg *ristypes.RISMessage) {
 	// Use the pre-parsed timestamp

internal/routewatch/peerhandler.go

@@ -8,6 +8,11 @@ import (
 	"git.eeqj.de/sneak/routewatch/internal/ristypes"
 )
 
+const (
+	// peerHandlerQueueSize is the queue capacity for peer tracking operations
+	peerHandlerQueueSize = 500
+)
+
 // PeerHandler tracks BGP peers from all message types
 type PeerHandler struct {
 	db     database.Store
@@ -27,6 +32,12 @@ func (h *PeerHandler) WantsMessage(_ string) bool {
 	return true
 }
 
+// QueueCapacity returns the desired queue capacity for this handler
+func (h *PeerHandler) QueueCapacity() int {
+	// Peer tracking is lightweight but involves database ops, use moderate queue
+	return peerHandlerQueueSize
+}
+
 // HandleMessage processes a message to track peer information
 func (h *PeerHandler) HandleMessage(msg *ristypes.RISMessage) {
 	// Parse peer ASN from string

internal/routewatch/routingtablehandler.go

@@ -9,6 +9,11 @@ import (
 	"github.com/google/uuid"
 )
 
+const (
+	// routingTableHandlerQueueSize is the queue capacity for in-memory routing table operations
+	routingTableHandlerQueueSize = 10000
+)
+
 // RoutingTableHandler handles BGP messages and updates the in-memory routing table
 type RoutingTableHandler struct {
 	rt     *routingtable.RoutingTable
@@ -29,6 +34,12 @@ func (h *RoutingTableHandler) WantsMessage(messageType string) bool {
 	return messageType == "UPDATE"
 }
 
+// QueueCapacity returns the desired queue capacity for this handler
+func (h *RoutingTableHandler) QueueCapacity() int {
+	// In-memory operations are very fast, so use a large queue
+	return routingTableHandlerQueueSize
+}
+
 // HandleMessage processes a RIS message and updates the routing table
 func (h *RoutingTableHandler) HandleMessage(msg *ristypes.RISMessage) {
 	// Use the pre-parsed timestamp