fix: resolve all compilation issues across transport and lifecycle packages

- Fixed duplicate type declarations in transport package
- Removed unused variables in lifecycle and dependency injection
- Fixed big.Int arithmetic operations in uniswap contracts
- Added missing methods to MetricsCollector (IncrementCounter, RecordLatency, etc.)
- Fixed jitter calculation in TCP transport retry logic
- Updated ComponentHealth field access to use transport type
- Ensured all core packages build successfully

All major compilation errors resolved:
✅ Transport package builds clean
✅ Lifecycle package builds clean
✅ Main MEV bot application builds clean
✅ Fixed method signature mismatches
✅ Resolved type conflicts and duplications

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

pkg/transport/message_bus.go

@@ -288,21 +288,7 @@ type TransportMetrics struct {
 	Latency          time.Duration
 }
 
-// MessageRouter handles message routing logic
-type MessageRouter struct {
-	rules        []RoutingRule
-	fallback     TransportType
-	loadBalancer LoadBalancer
-	mu           sync.RWMutex
-}
-
-// RoutingRule defines message routing logic
-type RoutingRule struct {
-	Condition MessageFilter
-	Transport TransportType
-	Priority  int
-	Enabled   bool
-}
+// Note: MessageRouter and RoutingRule are defined in router.go
 
 // LoadBalancer for transport selection
 type LoadBalancer interface {
@@ -328,26 +314,9 @@ type StoredMessage struct {
 	Processed bool
 }
 
-// DeadLetterQueue handles failed messages
-type DeadLetterQueue struct {
-	messages map[string][]*Message
-	config   DLQConfig
-	mu       sync.RWMutex
-}
+// Note: DeadLetterQueue and DLQConfig are defined in dlq.go
 
-// DLQConfig configures dead letter queue
-type DLQConfig struct {
-	MaxMessages   int
-	MaxRetries    int
-	RetentionTime time.Duration
-	AutoReprocess bool
-}
-
-// MetricsCollector gathers operational metrics
-type MetricsCollector struct {
-	metrics map[string]interface{}
-	mu      sync.RWMutex
-}
+// Note: MetricsCollector is defined in serialization.go
 
 // PersistenceLayer handles message persistence
 type PersistenceLayer interface {
@@ -415,20 +384,8 @@ func NewMessageRouter() *MessageRouter {
 	}
 }
 
-// NewDeadLetterQueue creates a new dead letter queue
-func NewDeadLetterQueue(config DLQConfig) *DeadLetterQueue {
-	return &DeadLetterQueue{
-		messages: make(map[string][]*Message),
-		config:   config,
-	}
-}
-
-// NewMetricsCollector creates a new metrics collector
-func NewMetricsCollector() *MetricsCollector {
-	return &MetricsCollector{
-		metrics: make(map[string]interface{}),
-	}
-}
+// Note: NewDeadLetterQueue is defined in dlq.go
+// Note: NewMetricsCollector is defined in serialization.go
 
 // Helper function to generate message ID
 func GenerateMessageID() string {