Refactor internal/server/user package structure

Co-authored-by: Roberto Abdelkader Martínez Pérez <robertomartinezp@gmail.com>

internal/server/user/state.go

@@ -1,36 +0,0 @@
-package user
-
-import (
-	"sync"
-
-	"github.com/BBVA/kapow/internal/server/model"
-)
-
-type safeRouteList struct {
-	rs []model.Route
-	m  *sync.RWMutex
-}
-
-var Routes = New()
-
-func New() safeRouteList {
-	return safeRouteList{
-		rs: []model.Route{},
-		m:  &sync.RWMutex{},
-	}
-}
-
-func (srl *safeRouteList) Append(r model.Route) {
-	srl.m.Lock()
-	srl.rs = append(srl.rs, r)
-	srl.m.Unlock()
-}
-
-func (srl *safeRouteList) Snapshot() []model.Route {
-	srl.m.RLock()
-	defer srl.m.RUnlock()
-
-	rs := make([]model.Route, len(srl.rs))
-	copy(rs, srl.rs)
-	return rs
-}