- Replace init() with config.Load() function when loading env variables
- Inject portRegistry into session, server, and lifecycle structs
- Inject sessionRegistry directly into interaction and lifecycle
- Remove SetSessionRegistry function and global port variables
- Pass ssh.Conn directly to forwarder constructor instead of lifecycle interface
- Pass user and closeFunc callback to interaction constructor instead of lifecycle interface
- Eliminate circular dependencies between lifecycle, forwarder, and interaction
- Remove setter methods (SetLifecycle) from forwarder and interaction interfaces
Only waited for one of two copy goroutines, leaking the second. Now waits
for both to complete before closing connections.
Fixes file descriptor leak causing 'too many open files' under load.
Fixes: #56
