feat(tunnel): switch to yamux stream proxying and connection pooling

- Introduce pooled tunnel sessions (TunnelID/DataConnect) on client/server
- Proxy HTTP/HTTPS via raw HTTP over yamux streams; pipe TCP streams directly
- Move UI/stats into internal/shared; refactor CLI tunnel helpers; drop msgpack/hpack legacy

internal/shared/protocol/adaptive.go

@@ -2,81 +2,23 @@ package protocol
 
 import (
 	"sync/atomic"
-	"time"
-
-	"drip/internal/shared/pool"
 )
 
-// AdaptivePoolManager dynamically adjusts buffer pool usage based on load
+// AdaptivePoolManager tracks active connections for load monitoring
 type AdaptivePoolManager struct {
-	activeConnections           atomic.Int64
-	currentThreshold            atomic.Int64
-	highLoadConnectionThreshold int64
-	midLoadConnectionThreshold  int64
-	midLoadThreshold            int64
-	highLoadThreshold           int64
+	activeConnections atomic.Int64
 }
 
-var globalAdaptiveManager = NewAdaptivePoolManager()
-
-func NewAdaptivePoolManager() *AdaptivePoolManager {
-	m := &AdaptivePoolManager{
-		highLoadConnectionThreshold: 300,
-		midLoadConnectionThreshold:  150,
-		midLoadThreshold:            int64(pool.SizeLarge),
-		highLoadThreshold:           int64(pool.SizeMedium),
-	}
-
-	m.currentThreshold.Store(m.midLoadThreshold)
-	go m.monitor()
-
-	return m
-}
-
-func (m *AdaptivePoolManager) monitor() {
-	ticker := time.NewTicker(1 * time.Second)
-	defer ticker.Stop()
-
-	for range ticker.C {
-		connections := m.activeConnections.Load()
-
-		if connections >= m.highLoadConnectionThreshold {
-			m.currentThreshold.Store(m.highLoadThreshold)
-		} else if connections < m.midLoadConnectionThreshold {
-			m.currentThreshold.Store(m.midLoadThreshold)
-		}
-		// Hysteresis zone (150-300): maintain current threshold
-	}
-}
-
-func (m *AdaptivePoolManager) GetThreshold() int {
-	return int(m.currentThreshold.Load())
-}
-
-func (m *AdaptivePoolManager) RegisterConnection() {
-	m.activeConnections.Add(1)
-}
-
-func (m *AdaptivePoolManager) UnregisterConnection() {
-	m.activeConnections.Add(-1)
-}
-
-func (m *AdaptivePoolManager) GetActiveConnections() int64 {
-	return m.activeConnections.Load()
-}
-
-func GetAdaptiveThreshold() int {
-	return globalAdaptiveManager.GetThreshold()
-}
+var globalAdaptiveManager = &AdaptivePoolManager{}
 
 func RegisterConnection() {
-	globalAdaptiveManager.RegisterConnection()
+	globalAdaptiveManager.activeConnections.Add(1)
 }
 
 func UnregisterConnection() {
-	globalAdaptiveManager.UnregisterConnection()
+	globalAdaptiveManager.activeConnections.Add(-1)
 }
 
 func GetActiveConnections() int64 {
-	return globalAdaptiveManager.GetActiveConnections()
+	return globalAdaptiveManager.activeConnections.Load()
 }