新增

• 新增"固定窗口大小"开关（窗口设置界面按钮 + /aws fixed 指令）：开启后把窗口当前大小完全锁死（最小=最大=当前值）。它不会跳变到配置分辨率、也不会强制居中——只是不能再改大小，并且标题栏最大化按钮会在系统层被禁用（GLFW_RESIZABLE=false，Windows 上移除 WS_MAXIMIZEBOX），从根上杜绝"假最大化"
• 窗口最大化或全屏时，固定窗口大小开关本身也会禁用（并给出提示），而不是去锁最大化时铺满屏幕的尺寸
• 全屏仍然可用（GLFW 全屏不受窗口尺寸限制约束），退出全屏后自动回到固定尺寸
• 固定窗口大小只受全屏/最大化禁用（临时禁用、退出恢复）；"配置分辨率过低"状态只禁用最小尺寸锁定，不影响固定窗口大小与居中（它们不依赖配置值）

说明

• 固定窗口大小为运行时开关（与最小尺寸锁定一致），默认关闭，重启游戏后恢复默认；固定开启时再点锁定按钮不产生额外效果（固定优先）
• 灵感来源：固定窗口大小的想法参考了模组 Locked Window Size（LGPL-3.0 协议）。本模组为独立实现，仅使用 GLFW 官方公开 API，未复制其任何源代码，因此仍以 MIT 协议开源。

Added

• New "Fixed Window Size" toggle (button in the Window Settings screen + /aws fixed command): when on, the window is frozen at its current size (min = max = current size). It does not jump to the configured resolution and does not force a recenter — it simply cannot be resized anymore, and the title-bar maximize button is disabled at the OS level (GLFW_RESIZABLE=false removes WS_MAXIMIZEBOX on Windows), so a "fake maximized" state is impossible
• The fixed-window-size toggle is itself disabled while the window is maximized or fullscreen (with an explanatory message), instead of trying to lock the full-screen-sized maximized dimensions
• Fullscreen still works (GLFW fullscreen is not bound by window size limits) and returns to the fixed size on exit
• Fixed window size is only blocked by fullscreen/maximized state (temporarily disabled, restored on exit). It is not affected by the "config resolution too low" state, which only disables the minimum size lock — fixed window size and centering keep working because they do not depend on the config value

Notes

• Fixed window size is a runtime toggle (same as the min size lock), off by default, reset on game restart; when fixed is on, the lock button has no additional effect (fixed takes priority)
• Inspiration: the fixed-window-size idea is inspired by the mod Locked Window Size (LGPL-3.0). It is an independent implementation using only the public GLFW API; no source code was copied, so this mod remains MIT-licensed.