refactor: drop Encryption, fix init order, simplify shutdown

- Remove unused Encryption class (AES wrapper around shit.zen.utils)
  and its construction from ZenClient bootstrap; drop dead TimerPatch
  import.
- Defer ConfigManager.loadAll() and CommandManager.initCommands() so
  configs load only after modules are registered, fixing values that
  were silently discarded.
- Make isOwner() return true so the local user is treated as owner.
- Rename ZenClient.disconnectFromServer() to shutdown() and pin the
  MinecraftPatch close hook to At.Type.HEAD so it runs before the
  game tears down its subsystems.
- README: invite users to file issues / open PRs for missing features.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

README.md

@@ -1,6 +1,6 @@
 # Open Zen [WIP]
 
-> 截止至目前，Open Zen仍然处于早期构建阶段。大量特性可能仍不可用，请谅解！
+> 截止至目前，Open Zen仍然处于早期构建阶段。大量特性可能仍不可用，请谅解！当您发现有不可用的功能，欢迎开Issues描述或直接提交Pull Request，我们将不胜感激！
 
 **Open Zen** 是 *Zen* Minecraft 客户端的反混淆源码版本，几乎是由 [Claude](https://claude.com/)协助逆向得到。目标版本为 **Minecraft 1.20.1 + Forge 47.4.20**。