v0.4.4

Fixed

• Fixed PHP Warning: Undefined array key in PtyManager::input() and PtyManager::resize():
  • Accessing $this->terminals[$id]?->... triggered PHP undefined array key warnings when frontend xterm.js resize listeners or lingering keystrokes arrived after a terminal session had exited and been unset.
  • Replaced with null-coalescing $this->terminals[$id] ?? null access to safely ignore input and resize operations on terminated or unknown terminal sessions without leaking warnings.