refactor(session): add registry to manage SSH sessions

- Implement thread-safe session registry with sync.RWMutex
- Add Registry interface for session management operations
- Support Get, Register, Update, and Remove session operations
- Enable dynamic slug updates for existing sessions

session/interaction/interaction.go

@@ -114,7 +114,7 @@ func (i *Interaction) SetChannel(channel ssh.Channel) {
 	i.channel = channel
 }
 
-func (i *Interaction) SetSlugModificator(modificator func(oldSlug, newSlug string) bool) {
+func (i *Interaction) SetSlugModificator(modificator func(oldSlug, newSlug string) (success bool)) {
 	i.updateClientSlug = modificator
 }